Hii,

The Basic eligibility to pursue Btech graduation degree is one must have passed 10+2 with Minimum 50% of marks.The Admission to various Engineering colleges depends on the  Entrance Test.JEE is the common entrance test to enter into the top colleges all over India. You will get NIT's if you get better marks in JEE mains.And for every state there is also a common Entrance test for engineering.

Thank you.