B.Tech

No, there is no any other exam.

Hi, Visit this link to check colleges based upon your rank:
https://www.shiksha.com/b-tech/resources/jee-mains-college-predictor
Good Luck. Hope it helps.

You should complete your Diploma first to get admission in any engineering colleges through lateral entry. You cannot leave your Diploma in second or third year. You have to study till third year in Diploma. You should not have any pending backlogs also to get admission in engineering colleges. Best of luck.

Refer the link:
https://www.shiksha.com/college/ambedkar-institute-of-advanced-communication-technologies-and-research-geeta-colony-Delhi-25189/admission
AIACTR will give much more experience in domains you want and will give more time so you have flexibility to allocate time to other activities apart from academics. Yes, it is one of the best institutes of Advanced Communication Technologies and Research.

It is not much tough, and is a good career option. Pursuing it in top colleges gives you good placement opportunities.

For answering your question, I am sharing a link below :
https://www.shiksha.com/b-tech/course/b-tech-in-tool-engineering-Delhi-institute-of-tool-engineering-okhla-175429.

CSE might be quite difficult for you to get, as there is heavy competition. There are some chances that you might get. If you try for other branches like ECE, Mech and EEE, you can easily get admission.

Exam will be held in the same college but exam is conducted by the university.

Yes, you do B.Tech in agriculture without studying maths in class 12th.

Visit the link below, you can use filters on location.
https://www.shiksha.com/b-tech/ranking/top-computer-science-engineering-colleges-in-india/46-2-0-0-0.