Engineering

There is no specific answer to this there is nothing to do with JEE Mains rank for the rank in JEE Advanced A good rank in JEE Mains can't get you a good rank in JEE Advanced It depends on many aspects like difficulty of the exam, preparation by your son, his dedication, clarity of concepts, the study material and coaching/Institute he has referred for the JEE Advanced exam.

If you are getting more than 1 Lacs rank it will be quite hard for you to get admission in DTU or NSIT. But still try your luck as there will still be some seats left for you to grab.
All the best for your admissions in them just try your luck. Upvote if you liked my answer.

Kindly elaborate your question, so that we can help you better.

B.Tech admissions are still open. Colleges like:
BML Munjal University, DIT University, Graphic Era, UPES, Doon University etc. Are having their admissions process.

Take a look at the following link to get a brief overview of Placement Highlights at DIT University https://www.dituniversity.edu.in/placements/placement-highlights.

Your stream should be science with PCM as compulsory subjects in your intermediate studies and you must me good in these. Some initial knowledge of programming may be an add on or a necessary requirement depending on the college you are applying for. For IITs and NITs initial coding knowledge is not compulsory, they teach from very basic level. Most of colleges allot CS branches based on your rank in there entrance exams. More Ever there is no such special requirement to apply for computer science and engineering.

For getting a seat in not the percentile should above 96 percentile, so he cannot get a seat in Nagpur.

Take a look at the following link: https://www.shiksha.com/engineering/colleges/distance-correspondence-diploma-courses-delhi-ncr