Tamil Nadu

Yes, to get admission in Chennai campus, you need to attend the counselling at the Chennai campus only. For all the campuses, you need to attend the counselling at Chennai campus only.
For NCR and Haryana campuses, you may go to the respective colleges.

Hello Abishek,
When it comes between VIT and SRM, VIT would be better than SRM University.
So you need to prefer VIT-Vellore to SRM University. VIT has better rankings and offers better education. It is known for its placements so you can prefer VIT Vellore for mechanical engineering.

NITs will not offer Diploma, they only offer Bachelor's degree and Master's degree. Try for some Hyderabad Universities or college like CBIT, VASAVI etc.

Yes, you can join Hindustan College of Arts and Science. It provides B.Sc in visual communication with all the necessary things. This department was established in 1999. The fee status is not in my knowledge.
For more information you may visit the official website of the college.

Hello,
Greetings from Shiksha!
CBIT is very good for you as it is having a good record, try for it. It also has a good placement, if you have an opportunity go for it. Hope your doubts are clear, good luck!

Hello,
Greetings from Shiksha!
Check for NIT, Trichy and NIT, Madras if you had given your JEE Mains or Advanced else you can have VIT, SRM, Geetham, Sastra University, etc. which have a good career for CSE. Kindly have a look at theses institutes as well. Good luck!

Which entrance exam are you talking about?

Your rank will be around 20000 so you may get the main campus of SRM University. You can easily get other campuses with this rank.
The branches at main campus may not be good for your rank. You may get chemical engineering, civil engineering, mechatronics, etc. but at the other campuses you can get all the courses.

If you are specifically aligned to CSE and if you are getting it in NIT, Raipur then go for it, otherwise if branch is not an issue and you are targeting for knowledge then mechanical engineering is one of oldest and good branches of NIT, Raipur.