Dear Kaviya, now NEET is the entrance examination for admission into all Medical, Dental and Ayush colleges across India. Around 400 colleges participate in this exam for their respective seats in both All India and State Counselling Seats. Then there is AIIMS entrance examination for admission into all its branches including AIIMS, Delhi. JIPMER is another entrance examination. Many prestigious Medical Colleges like AFMC conduct admissions into their colleges based on NEET score. 

Hey there, You have only three entrance exams after your 12th grade. NEET is the sibgle extensive entrance exam that covers the admission for all MBBS and BDS exams in india except AIIMS and JIPMER

AIIMS and JIPMER conduct their own entrance exams every year. hope this helps. Good luck