There are only three Medical entrance exam NEET, AIIMS, JIPMER. As per the eligibillity to apply for NEET entrance exam you should have minimum 50% in class 12th as a General category, for AIIMS you should have minimum 60% as a General category and for JIPMER you should have minimum 50%. To check the further eligibility of the exams you can go through with the given below links.

NEET Eligibility

AIIMS Eligibility

JIPMER Eligibility

Good Luck!