After decades I am still uncertain of some grammatical rules and word choices. I still struggle with spelling often, and once in a while I find a word that I have been pronouncing wrong my whole life.

Get more contact with native speakers. No shade but half of them don’t even know the rules

I know how you feel, I also feel that. I am not always sure how to navigate cultural connotations of words, sometimes a native surprises me by using a phrase, that I have known before, in a way that I knew is the proper use but would have never come up with that myself. Yet, since I started spending more personal time with native speakers, I would often be asked to take a look at a draft of their message. Or they ask me how would I word something. Because “you are better with words” ¯\(ツ)/¯ The difference is, you and I pay attention to what/how we say it. Native speakers often just say it as it comes

Granted, as we already established, I am not a native speaker but by looking at your posts I would not say you are struggling with English