To take admission in National Institute of Technology, you have to give jee mains.
I am enclosing here the jee mains brochure.Go through it and then take the informed choice.
https://jeemain.nic.in/WebInfo/Handler/FileHandler.ashx?i=File&ii=88&iii=Y
Open this link and go through it
Regular exam updates, QnA, Predictors, College Applications & E-books now on your Mobile