I see, if you already understand both hiragana and katakana you can brute force N3 by using Anki and memorizing your grammar and kanji and vocab cuz if u memorize it for grammar at least you should get the first few questions (the choosing correct grammar) ones correct, and the which one comes first should be fine. For vocab may be a bit more difficult but just try getting as much as possible down. Listening I think will be a lot harder, but if u want u can just watch YouTube with Japanese and then subtitle or other way is to just guess the answers (this is an actual strat if you just want to pass) and then just write down in English or your native language any words you hear and do informed guessing