NIT

Only 4 IITs offers B.Tech aerospace engineering degree:
1) IIT Kharagpur
2) IIT Kanpur
3) IIT Bombay
4) IIT Madras
5) IIST (under ISRO)
6) IISC (Only for M.Tech they offered aerospace engineering)
If you got any queries, ask questions in comment section.

For taking admission in IIT, you will need a rank below 1500 and marks at least 250+ in JEE advance to get easy admission in aeronautical engineering. I hope this will help you.
Good luck.

Yes, if you have done your graduation with computer Science/computer application stream then you are eligible for MCA at NITs. Good luck.

No, it is not possible for you to get into NIT or IIIT. Even if you have reservation, it would be hard for you to get a seat.

Of course. It is an NIT after all. It is a very good college. Also, not very easy to get.

The validity of the MAT score is 1 year so you can apply with the score next year.

The best option would be to join a coaching institute. They will tutor you accordingly and they will helo you to understand complex concepts while preparing. Be prepared to give your best and study your BCA course thoroughly too. Study at least 2 to 3 hours daily and solve practice papers.

It will be from 2019 onwards.

The announcement by MHRD, the revised criteria of 75% marks (Gen Category), 65% (SC/ST/PwD Category) or being in the top 20 percentile in class XII is likely to be applicable for admissions to all NITs/IIITs/GFTIs along with IITs from the admission year 2017-18 onwards.