I had English in school for many years, but that wasn't where I learned English. As stupid as it may sound, I learned English from watching YouTube videos about topics I was already interested in and already knew a lot about. That made it easier for me, because I only had to connect the information I already knew with the new words and phrases of the English language. With time - we are talking some years here - my understanding of the English language became better. Right now, I would say I understand 99.5% when people talk English and I'd like to think I speak English relatively well. I do understand English a lot better than I speak it though.
Listen to people who speak more + you enjoy listening to them I would say this is the best way to learn how the structure of any language works
Watch English shows, listen to English music, and listen to English speaking people talk. Your written English seems pretty good btw. Better than mine lol
I agree. If you get a one on one tutor you are going to make way more progress way faster. If you have the money, you should always err on the side of getting a tutor/coach/personal trainer/etc. Time is a more valuable resource and the right professional will save you an immense amount of time. Our species is literally as powerful as we are because we learned from people who knew more than us.