I don’t know shit about Cantonese and the only mandarin I know is the most basic of phrases and stuff to refer to food (so essentially nothing) so I can’t speak to that

Japanese is hard, but so is any language. You get out what you put in. I wasted about a year with “studying” half assed for like 10-15 minutes a day with duolingo. It was good that I had a consistent routine but at the end of 1 year I had very little to show for my effort. Learn from my mistake.

After that I switched things up. I didn’t put in a ton more time but I changed approach. Pretty standard but boring stuff: Anki, Assimil, and some other more targeted apps later on (renshuu, Benkyō, and most recently kanji dojo have been helpful). Setting up language exchange calls via apps like hello talk and discord have been far more helpful as things have progressed. This is more of a significant time investment and requires me to teach English a bit but I am happy to do it for free Japanese instruction. Joining group chats on line, watching YouTubers and vtubers, anime and dramas, etc also is helpful but the hard part was determining when to make the jump to not use subtitles and finding content that was digestible at my level. I’m not the kind of weeb that watches precure and little kid shows but for a minute I did just to watch stuff without subs. It sucked.

After about 5 years I got decent enough to have solid conversations via phone and text. Then DeepL came out and made it all pointless haha