Dear Ajay, you havent mentioned the course that you want to take up in B.Sc or the college that you want to join. But in generic terms, most colleges dont have Age limit. Having said that it totally depends on the University/Institution that you want to study in. Most Institutions prefer a minimum aggregate of 50% in your 10+2 as qualification. Few Institutions conduct Entrance Exams and few conduct admissions based on the merit in your 10+2. So you can apply to colleges though you have gap years