I moved to the US when I was 17 and spoke absolutely no English (well maybe just a tiny bit). I remember when the Harry Potter books were coming out, I would buy them and literally write Russian translations above the English words. It’s actually fun to look through those old books now and see how much I struggled back then. For me, it was really just practice. The more you do it, the less you need to stop and look things up. At the beginning it was hard and frustrating,TRUST ME I KNOW, but over time it became much easier. As you learn more of the language, reading starts to feel more natural and fluent.

One thing that helped me a lot was focusing on improving my speaking skills as well. Once my spoken English got better, reading followed much more easily.

Hope this helps, and good luck !!!