I know hiragana and katakana, but not that many words or grammar. I wanted to play Pokemon FireRed, but when i tried it was a fail - I wasn’t at that level yet. So, I made something to help me. Maybe it’ll help you too.
I made a free flashcards deck with EVERY WORD of Pokémon FireRed in Japanese, IN THE ORDER you meet it in the game. You study a stretch, then play it and are able to read it.
0. Learn hiragana and katakana (you can do it quickly on Duolingo or however you like)
1. Install Anki (also on Android and iOS)
2. Get the deck: Pokémon FireRed in Japanese on AnkiWeb
3. Study some cards
4. Play the Japanese version of Pokémon FireRed up to where your cards have got to
5. go to 3.
Each card is a sentence from the game with one word highlighted. The back gives the word’s dictionary form and kanji and teaches you what it means in that sentence, how the form is built and the grammar. It also shows the full sentence in kanji and in English.
The whole story (with dialogues, UI, Pokemon names, etc.) is 9,537 cards. The Help menu and the multiplayer text are separate decks.
Source and how it is made: github.com/mkusm/pokemon-firered-jp-anki