Hello Aspirant,

If you are asking to take admission for B.tech programme again in National Institute of Technology.

NITs takes the admission through JEE Main entrance Exam. As per the eligibility to apply for JEE Main 2020, You should have passed class 12 or qualifying the exam in 2018 or 2019. You should have minimum of 75% marks in class 12 or equivalent exam or you must be in the top 20 percentile in your class 12 examination.

You can check the complete eligibility of the exam to go through with the given below link.

https://engineering.careers360.com/articles/jee-main-eligibility-criteria

If you are asking for M.tech admission in NITs then the admission is through GATE Entrance Exam. As per the eligibility to appear for GATE, You should be qualified or in final year of Bachelor in Engineering/Technology.

To check the complete eligibility, You can go through with the given below link.

https://engineering.careers360.com/exams/gate

Good Luck!