Hey Mouli

I'm sorry to say but at this rank of yours, it is really difficult to get admission to any of the NITs. Although under OBC quota, there is a slight chance of getting a seat in GFTIs, specially under the spot round. Also, it would not be possible for you to get the top branches here. Thus,  if you have a branch preference, then you could look up for private institutions as well. There are a lot of private institutions that give admission through JEE MAINS score, and many others which give admission on the basis of their own entrance examination. You can search about these colleges. 

Also, you can check for the possibilities through the college predictor. Given below is the link for the same

https://engineering.careers360.com/jee-main-college-predictor?utm_source=google-search&utm_medium=paid&utm_campaign=jeemain-clgpd

Also, I'm providing the link for the list of private colleges that give admission through JEE mains 

https://engineering.careers360.com/colleges/ranking/top-private-engineering-colleges-in-India-accepting-jee-main-score

I hope this helps. 

All the very best!!