Look into Comprehensible Input. Dreaming Spanish is a great channel/site.

It's really not difficult to do per se, it just takes a LOT of time. 1500+ hours. But if you can replace the time you spend watching YouTube videos and doomscrolling, you'll get there eventually. Especially once you reach the point of understanding media in the language you're learning. You can then go mindlessly watch YouTube again... but in that language lmao.

Check out this playlist for an explanation of the method (turn on subtitles) https://youtube.com/playlist?list=PLlpPf-YgbU7GrtxQ9yde-J2tfxJDvReNf , TL;DW don't study the language. Don't do grammar/vocab by rote. Literally just listen to a crap ton of the language. You will learn grammar/vocab naturally with repetition in context. But you must listen/watch at a level you can understand. That starts with content with a lot of hand gestures and simple stories, where maybe you don't understand the words but you understand the meaning by the rest of the context. After a hundred hours or so you can move on to content with less context clues, and after maybe 400-600 hours start with media meant for native speakers.