Dear Aspirant,

It is very difficult to get NITs or IITs with a JEE Mains score of 86.91 percentile even in CSAB counselling. The only chance is when you belong to the home state of any of the NITs or IIITs which have relatively low cutoff compared to the other ones. So you should try for other colleges and state universities which accept JEE Mains score.

You can use the JEE Mains college predictor to explore your options - https://engineering.careers360.com/jee-main-college-predictor?icn=QnA&ici=qna_answer

Good Luck!