Hey there

Admission in nits or iiits are not on the basis of but on the basis of rank. From previous few years the cutoffs vary in not a uniform way. For admissions in nits or iiits your rank must be lower than 30000 which I am considering for lower nits and iiits. For good nits and iiits your rank should be good atleast less than 15000.

Check about JEE mains

https://www.google.com/url?sa=t&source=web&rct=j&url=https://engineering.careers360.com/exams/jee-main&ved=2ahUKEwjn7vqw9drkAhXTV30KHQrWDlAQFjAAegQIAhAB&usg=AOvVaw1k3rMyr-Osb0qy4gsPfOaR&cshid=1568829145134

Good luck