Yes, you are eligible for JEE Main exam to take admission in NITs/IITs and IIITs.

To check the complete eligibility criteria you can refer below

-It is mandatory for candidates to have taken 5 subjects in 12thor qualifying exam

-The 5 subjects for B.Tech/ B.E. are:

1-Language, 2-Physics, 3-Mathematics, 4-Any one of (Chemistry, Biology, Biotechnology, Technical Vocational Subject), 5-Any other subject

-A JEE Main candidate can avail 3 attempts for the national level undergraduate engineering entrance exam.

-Students who are born on or after October 1, 1993 are eligible

-Candidates must have passed 12thclass. Appearing students are also eligible.

Good Luck!!