Learn Japanese

I really like Cure Dolly's approach though the videos are a bit difficult to understand with her accent and the quality which is why I linked the transcript, I find that more useful anyway personally. Her approach to the language really clicked for me though. That and the Kaishi 1.5k Anki deck for vocabulary has gotten me pretty far.

I think also immersion is super important. Once you learn the kana, you can jump right in to reading with some free, simple books for children at Tadoku and use jisho.org to look stuff up. It's slow work but very rewarding imo. I'm doing manga translations now for practice after working through some of those. I also watch anime and try to ignore the subtitles and listen for common phrases and whatnot as listening is a separate skill that needs to be trained.

One thing I actually think apps like Duolingo are good at is teaching the kana, which is usually the biggest hurdle most people seem to have in the beginning. I used Duolingo for that and it helped me at first but it does a bad job with everything else IMO, especially grammar. I'm sure there are other apps for teaching hiragana and katakana, or an Anki deck probably exists too if that's preferable.

I'm far from functional with the language but in the year I've been studying (honestly pretty lazily) I've improved a lot and I haven't spent a dime.