I am a 10th student. And a medical aspirant. Will choosing biopsychology in my 11th grade help me in achieving my ambition?

I see you are in Kuwait, I am not sure if the years match as they do in the US but it you are looking to take  specialized class as a Junior in High School and that education is either free or the class an available elective I would recommend you taking it. That is IF you are sure you want to be in that general field. The reason being is by taking it you may realize during the class that is not the concentrated field of Scientific study you would like to focus on. Furthermore it may also help you discover what specific field you do want to study. It is much better to find that out earlier, and possibly for free, rather than waiting to get to a University where you are paying for it. Hope this helps.