My recommendation is to SING! Yes, listen to a song in English and repeat it. It’s a fun way to listen and accustom your ear as well as exercise the pronunciation.
I myself speak four languages fluently, Spanish, English, French and Portuguese, and it works.
Start with easy songs and work your way up. There are a lot of options in youtube and you can search for the lyrics to follow the exact words of the song.
Here is a link to an article that refers to this. https://learningenglish.voanews.com/a/brain-remembers-language-sing/2776476.html
Best of luck with this.
I am Portuguese and, therefore, English is not my main language. Since I was a little boy, I realised that if you attentively listen to music and movies in English, it will help you a lot! Obviously, having English classes at school was also important, as it allows you to understand the language structure and the basic elements (also, grammar!). But it's vital that you have the interest to learn and be keen to improve it! Another thing I used to do with my Portuguese friends was having conversations between us in English. That way, you can learn with other people's knowledge and practice! So, in the end, I would recommend you to put your heart in it. Just find interesting and funny ways to do it and don't look at it as an obligation!
Even today I feel the need (and the will!) to keep improving my English. Thus, I moved to a foreign country where English is the main language and I keep reading written content in English (I read a lot of online content - such as news, articles or anything that I like to read about in English - and every time I buy a book, I get the English version (and not the Portuguese one).
Hope this helps! Good luck!
I feel like reading as much as you can is the best way to get a good grasp on the English language. Also, discussing what you've read and even handwriting a summary of what you read. Don't be afraid to ask questions either!
If you have a hobby, find a way to incorporate English into it. Or conversely, look for a new interest/hobby, one that'll naturally have you brush up your English.
Chances of picking up a new language increase will increase in this manner.
All the best!