Hi Prathamesh,
You haven't mentioned your home state, and the branch you want to choose.
However chances are very less to be very honest with you. You will not get admission in any of the NITs with 21k OBC rank.
You can check cutoff at:
https://engineering.careers360.com/articles/nits-cutoff-for-top-btech-branches
Your admission in IIITs or GFTIs is also tough and even if you get admission, you may not get the course of your choice.
For cutoff, please follow:
https://engineering.careers360.com/articles/jee-main-cutoff-for-top-iiits
You can use our college predictor to predict the best college for you:
JEE Main College Predictor – Know your College Admission Chances Based ...
Hope this helps!
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