You have a good foundation, so you'd better focus on languages, because you still need language scores to apply for universities, but you can also apply for university exams. I don't know anywhere else, but what is taught in high schools in North America is still very simple. As long as you have passed the language test, there is no problem in a first-class university. I suggest you find a public high school yourself. Although it's a little hard at first, you can improve your English quickly, so don't worry about it in the future.