Greetings!

91 is a respectable percentile, however it is not enough to make into NIT Calicut, due to OBC and homestate quota, he may get some other lower branches like production engineering or something of that sort, getting CSE or electrical related branches is not going to be possible

You can use the following predictor to see which colleges he can get

https://engineering.careers360.com/jee-main-college-predictor?utm_source=qna&utm_medium=jee_cp