Dear Nithya, you haven't mentioned which entrance exam you are talking about.  In India to become a doctor, you should study MBBS. There are 3 medical entrance examinations that you can choose from to appear and qualify. They are NEET, AIIMS and JIPMER.
AIIMS: There are around 1200 seats for around 14 branches. If you belong to General Cateegory and OBC you should score 60% in Physics, Chemistry, Biology and English. It is 50% for SC,ST and 45% for PWD.
JIPMER: There are around 200 seats for 2 branches. If you belong to General Category or EWS, you should score 50% in Physics, Chemistry and Biology. It is 40% for SC,ST,OBC,PWD and 45% for General PWD.
NEET: There are around 61,000 medical sears across 450 medical colleges across India. If you belong to General Category, you should have a minimum aggregate of 50% in Physics, Chemistry and Biology. It is 45% for PWD and 40% for SC, ST, OBC.