NIT Trichy - National Institute of Technology

Check the link and click on know college cut off option :
https://www.shiksha.com/jee-mains-college-predictor

CEPT is the best to pursue B.Arch.

Use the links mentioned below
https://www.resonance.ac.in/jee-main-answer-key-solutions/jee-main-2016-rank-predictor.php
https://www.shiksha.com/jee-mains-college-predictor

CSE NITT is the better option

Yes, you will get a seat. Apply for NITT ECE too for back up. You will need a OC rank of 1500, but OBC rank varies widely.

I've heard that IIITH is very good for CSE. But facilities in NITT for CSE along with placements are good.

You will need a JEE score around 180-200 to secure a seat.

I don't think that mains score is enough to secure a seat. You will need around 180-200 for that.

Dear Nijith,
Both the institutes mentioned by you are equally good and thus it will be very difficult to tell which one will be the best option. However, we can help you with the parameters that you can keep in mind while choosing an institute among them. You can consider the below parameters :
1) Faculty,
2) Affiliation / Recognition
3) Course Material,
4) Quality Education,
5) Fees
6) Infrastructure
7) Success Rate.
8) Placement
9) Top recruiting companies.
Also, if possible go through the alumni speak section to get an idea what the alumni thinks about the institute.
Hope this information helps. Please feel free to revert.
Wish you luck.