https://djtguide.github.io/learn/guide.html
Well uhh you can consult this for most of your problems
As somebody just starting out you'll want to learn kana first, I recommend using this https://djtguide.github.io/learn/kana.html and just go through it everyday. How fast you can drill it sufficiently depends on how much time you spend on it but I would say that the fastest you can expect is 3 days, and you absolutely should finish within two weeks which is exactly how long it took my lazy self
Note that even after you learn kana you'll have an abysmal reading speed with them and you'll frequently mess up stuff like し x レ, ノ x ソ etc. It'll take you a long time to iron these out but don't worry about it
You'll also want to learn grammar to some level, I recommend Tae Kim's guide. You should definitely read the part about particles at the least. In general I think you can be pretty loose about grammar, going through Kim's guide or some other basic and short thing first and then consulting some other slightly more detailed digest book whenever you're reading and don't get the grammar in a sentence. I've seen people do stuff like hour long daily grammar drills and whatnot for both Japanese and other languages an it seems like a complete waste of time to me, I wouldn't recommend it. If you absolutely don't want to bother with grammar you can just completely abandon it and bruteforce the whole thing through sheer immersion but I wouldn't recommend that either.
For vocabulary acquisition you'll have two sources. The first is Rikaitan(formerly yomitan(formerly yomichan) which is a pop-up dictionary. I would say you absolutely need this and you'll be using it a shitlot everyday. Make sure to go through the settings and make it as easily usable for you as possible, and to go through the dictionaries available to find some that look decent. The idea is simply that you'll run into words in and out of your browser and run them through the dictionary gradually learning them as you keep running into the same words over and over again.
Next is Anki, which is a bit different since rather than "learning" through immersion as above you're going through words and sentences in a way somewhat seperated from their actual context. It's a mix of learning the words and just going through a quick primer so that you won't struggle as much when the words you encountered in Anki appear in front of you while you're immersing. I've seen a lot of people criticize Anki saying the time is better spent on immersion, or that it causes people to give up on Japanese because going through their daily Anki session is too much of a pain. I think these are both perfectly fair arguments, but I still think Anki does genuinely help learning.
If you want you can completely ignore Anki and never bother, or just do as much as you feel like whether that be a single 1500 word deck or a 15k one, or alternatively never bother with premade decks and exclusively use Anki with a mining deck. Personally I would suggest that you either go through the Ankidrone Essentials deck or the Core 2k/6k(or alternatively 2k/6k/10k one which is just the same with 4k more words, I would suggest that if you want core that you go with the 10k one instead since it's just the same thing but without the risk of getting a big mess should you finish 2k/6k and then later want to do 2k/6k/10k as I did) and VN Core 1250 as a supplementary deck while you progress through whichever main deck you picked. The reason I'm suggesting a supplementary deck is because every deck I tried was meme shit where there's a lot of useless rare words and plenty of very important words misplaced in the order. I assume Ankidrone, which is some brand new stuff I've never tried, suffers from the exact same issue. Having a supplementary of some sort helps fix the issue somewhat. Do note that you're not restricted to VN Core and can just use whatever stuff you want if you ever feel like it. See https://jpdb.io/prebuilt_decks
I can't help you with mining decks since I never used them so you'll have to test it yourself or ask somebody else. They seem to be fairly popular and I can kind of see the point, but I don't think they're absolutely necessary. I did do something similar, where as you can see in my image is just lining up a lot of words that I either do not know the reading or meaning of which I happened to see while immersing in the language. I would lob them all in a tab of my browser and go through it at least a dozen times everyday, trying to remember both the reading and meaning of the words one by one, looking them up with my pop-up dictionary to see if I got them right, then deleting those words which I'm sure I memorized and also regularly adding more new words I encounter. I would say it's a quick and dirty version of mining, and I think it helped me a lot. If you try to mine properly you can effortlessly make an Anki card with the word you're mining, the sentence it's in, a screenshot of the manga or a clip of the anime you found it in etc though. What I'm showing you is a .txt opened on my browser which requires you to fiddle with the .txt itself to edit it which is inconvenient. In the past I would list the words up on Google Translate instead since it was more convenient to keep a list of easily editable words on there for a long time but they changed some stuff. If you ever feel like trying this out it'd be easier for you if you could find a good site for it.
Regarding how to use Anki, see https://djtguide.github.io/learn/anki.html
Picrel is a screenshot of my deck setting, which was originally based on what was written on that page but is now I believe slightly different. There's some stuff on default there like the "easy days" part since I stopped using Anki before I that stuff got implemented. I think that how you use Anki is very important and you should read the docs and experiment a little to see what works for you. One of my favourite parts about my settings is how I can defacto reset a known card and just keep repeating it over and over again by pressing "again" until I feel I've remembered it.
For daily cards I suggest 15-30. Ideally you'll be going with at least 20 per day, you can temporarily drop down to 15 if you feel overwhelmed, and if you feel that it's easy you can go above 20. Going above 30 is viable, but I wouldn't recommend it to somebody who doesn't know what he's doing. I went all the way up to 60 for Japanese and 100 for Chinese back in the day and it's a really volatile wild ride. You might want to do 20 cards on your main deck and 10 on your supplementary I suppose. You'll want to take about 30-40 minutes for your daily 20 cards + reviews. Faster is of course better. I don't know what your situation is like, but I would say that an hour a day of Anki is the max amount of time you should spend on it if you spend less than maybe 5 hours immersing in the language. You can raise your daily cards and go above that to a max of 2 hours of Anki everyday if you spend more than 5 hours immersing. I wouldn't recommend any more Anki than that as it's a supplementary tool that helps you learn the language and not how you learn the language. When you open a deck you'll find lots of stuff like example sentences that are read aloud, images that serve as tips etc. You can add and remove that stuff as you like, personally I didn't have any images in the decks I used, turned off the audio, ignored the sentences, and listened to good music everyday while doing my reps.
When you've finished up the kana and (if you bothered) read a grammar guide and set up your Anki, you can either wait until you rack up 500-1000 words in Anki or just dive right into immersion. I'd say go with whichever you want, it's not that big of a choice since you'll get completely fucked either way. I would suggest that you start with reading since it's easier with how everything is clearly presented as text allowing you to both easily look stuff up and not worry about pausing nonstop like you would do with audio or anime. Specifically I think manga and VNs are good for learning, if you can enjoy Yotsubato I would recommend it. For VNs you might want something like the Steam version of Little Busters with how it allows you to switch between languages instantly with a single click, or Yuzu games that recently both have official English translations and also allow you to have two languages displayed at all times. They aren't the only ones doing this either, so if you find their games boring as fuck you can try another one from a different place. For the record I don't think there are any "beginner-friendly" manga or VNs or anything really, just standard ones and ones that use the language in a way that can easily fuck somebody without a firm grasp over really hard. So long as you avoid fancy chuuni shit you should be in the clear, there's no need to worry too much about difficulty and you should instead focus on enjoying what you're doing and getting the most out of it language-wise.
Anime wouldn't be bad either, although it'll be a struggle for you for a myriad of reasons. You might want to keep it to a level where you're definitely going through anime in Japanese, but still frequently watching with English subs. There's no point if trying to learn the language makes you sick and tired of the stuff you want to engage with in the language. I'll post some links for where you can find Japanese subs later, it seems to me though that it's more efficient to find releases with Japanese subtitles than to look for subs in external sites. I know for a fact that both Amazon and AT-X have Japanese subtitles on all their stuff, so any release from them is going to come with Japanese subs.
I don't know what you plan on doing with the language but I recommend you focus primarily on your reading ability. Over time you should be naturally shifting to listening ability and gaining the leeway to really bother with shows and anime with JP subs which will rapidly boost your listening ability. You don't need to bother with writing at all if you do not plan on physically writing something in Japanese. For output(speaking, writing) I advise that you don't bother with it until you get to a good enough level with your ability read and listen. Maybe start doing output exercises after a year passes? If you have even the slightest desire to output in the language you'll want to get around to that eventually since you will otherwise fumble and eventually force your way into being able to speak and write after over 10k hours of immersing in the language, which is acceptable but not ideal. I did just that and while I can speak to Japs just fine now there's still a bit of awkwardness, in part because I still rarely talk to them even now.
That'll be it I guess feel free to ask me any questions or ask for games/manga/LNs that you can't find etc. I have fucked around a fair bit and I can do some cool stuff like showing you how to pirate Jap TV and find live watchtogethers with the Japs on futaba or showing you how to watch free gay porn on niconico or whatever
And obviously make sure you check imageboards and reddit or whatever the fuck for advice and useful projects and whatnot too, there's a lot of weirdos out there still making shit like perfectly automated machines that upload subtitles directly into your brain or whatever, and surely there's ways to get AI to help you analyze sentences in a decent way too. I didn't care about fancy shit when I was learning and I've had 0 reason to even bother knowing they exist for years now but they may be useful to you now
https://dlraw.app/
https://zi0.cc/
https://kitsunekko.net
https://jimaku.cc/
https://news.web.nhk/news/easy/ (<-- i recommend you go through this it's the news but with baby japanese, it should help you a lot with absorbing basic grammar)
You can try the /djt/ and /lang/ on /int/ as well as the smugloli and maybe the traschan /djt/ too