This is going to be super long because I love to yap about language learning, sorry in advance.
I've always been interested in foreign languages and my dad is an otaku who pumped my brain full of anime and J-music before I could even form a coherent thought, so learning Japanese has always been kind of a plan I had in the back of my head growing up.
I tried teaching myself, but I didn't have the discipline for it because it was too boring for me to follow textbooks & I didn't have the pressure needed to take it seriously, so it's only when I got into uni being dead set on pursuing translation as a career that I was able to actually make significant progress. Along the way, I started working on fan TLs as extra practice.
After that though, my philosophy has always been "rawdogging" the language and jumping straight into what interested me, since that's what sticks with me and that's how I ended up learning English. Basically, immersion all the way. I get to learn AND I get to see fictional guys I can rotate in my head like a dish in a microwave, yippee! So, yeah, games (especially gacha games, unfortunately) were a huge part of that practice material.
Making JP-speaking friends is also a source of motivation, too, but I haven't really been successful in that regard yet because I developed massive anxiety and impostor syndrome over the years, so I'm still working on it.
When it comes to learning tips, I'd say your first steps should be learning hiragana and katakana alongside basic grammar, and working your way up from there. When it comes to learning kanji, I personally think it's more effective to learn vocabulary including kanji in context rather than learning them on their own since it makes them easier to remember (for example, it's easier to remember the word "name" if you see it in the sentence "My name is John" than if you just had a flashcard with the word "name" on it—that kind of logic). I'd recommend checking out the resources that have been linked on this thread already, they're nice!
When it comes to tools, I like to keep things simple for my personal setup: Yomitan, Anki, a text hooker, a VN I wanna play, and I go to town with that. I only use a VN-specific setup because I'm too lazy to bother having a setup for other things. Here's what each of those things do, assuming you're not familiar with them:
- Yomitan: A browser extension that allows you to hover over a word to get its definition. You can install a lot of different dictionaries on it. If you use Anki alongside Yomitan, you can use Yomitan to create flashcards directly on Anki, which will allow you to review them.
- Anki: If you want to learn JP vocabulary, Anki is going to be both your best friend and your worst enemy depending on your perspective. It's a SRS flashcard program that allows you to make your own flashcards and review them, and there are a lot of resources out there meant to facilitate what language learners call "mining", basically adding the new words that you come across while immersing to Anki to review them later. There are even pre-made vocabulary decks that you can import to kickstart your vocabulary learning by making you study the most common vocabulary out there, like the Kaishi 1.5K deck.
- A text hooker: This is a piece of software that connects to the VN you're playing on your computer and extracts the game's text so you can copy it and paste it somewhere else. You'll want to use it with a browser text hooker page so you can use Yomitan on the words you don't know. There are different text hookers out there, but I think nowadays the most up-to-date with most VN text engines is LunaHook (if I'm not mistaken, at least).
While MTL can be comforting to a beginner, I wouldn't recommend it at all if you want to study Japanese seriously because you risk using it as a crutch and relying on it too much in the long run.
Also, if you want to go for immersion, it's important to pick something that's a nice balance between something that's within your skill level and something you're actually interested in, because there's no point in picking something that's easy if it bores you to death, and diving straight into something too hard even if you're interested could discourage you in your studies. For otome games, for example, I'd suggest starting out with a slice of life game if you enjoy the genre because the Japanese in those games will generally be easier to understand than a fantasy or historical game.
This post is getting dangerously close to 1k words so I'll end it here, but to finish off: don't compare yourself to others in your language learning journey if you treasure your mental health. We all learn at different paces, and you shouldn't beat yourself up if you think you're slow. What matters is that the process should be fun for you, even if it's going to take a long time and self-discipline to get to a place where you feel comfortable playing games in Japanese. Good luck on your journey, fellow traveler!