i have got 97.8 percentile in jee mains paper 2 , can i get any top nits , i belong to OBC-NCL category?!

Hey aspirant!

To calculate your expected rank for B.Arch based on the percentile score that you have secured, you can use this formula:

(100 - your total percentile score) is the percentage of people ahead of you. Also, 112679 were the number of candidates who appeared for January exam.

So rank formula is (100 - your total score) X 112679 /100.

In your case the expected rank comes out to be around 2478. To be honest, that is a very goid score and rank and your chances of admission to a good NIT is high. However, the cutoff of different NITs also depend on the home state and gender considerations.
Nevertheless, according to previous year's cutoff, the NITs which you may get for this rank are( some of them only if you belong to their home state):-
NIT HAMIRPUR
NIT JAIPUR
NIT RAIPUR
NIT PATNA
NIT BHOPAL(small chances)
Also, if you belong to home state of NIT Rourkela, you may stand a chance to get admission in it. If you want to see the previous years' cutoff trends, you can visit the link
https://www.google.com/amp/s/engineering.careers360.com/articles/jee-main-cutoff-for-b-arch-b-planning/amp
Also, you can use this college predictor to predict your chances of getting your dream college
https://engineering.careers360.com/jee-main-architecture-college-predictor