I came to America last year , so how many year will I speak English fluently ?
For the rest of your life.
it depends on how often you communicate to people.
This depends if you are seeking education in English language or learning by practice. I don't think anyone can tell you if you would be able; perhaps you should set a goal to speak fluently in 12 months or something then work towards this vision.
Watch your favorite television show or video, and learn words. Comedy works, or soap opera. Welcome to your new home! You will do well because you seek answers!
You are already doing fine. Welcome!