Hii,

To appear in KVPY after 12, one should have scored an Aggregate 60% (50% for SC/ST/PWD) in Maths and science subjects in class 12th exams. So you will have to score 60 or 50% as per your category to appear for KVPY exam under SB category. you must be enrolled in 1st year of an undergraduate program in basic science. Check KVPY eligibility criteria for more information.

Hope it's sufficient!!!