Thapar University

Hi Varma Abhinav, yes you really have great chances to get admission in all of these colleges.
You can get SASTRA University under stream 1 as it includes both JEE main or and board exam marks for admission.
B.S Abdur rahman conducts entrance exam called BSAUEEE for admissions into B.Tech programmes but it also accepts JEE main scores so you can get that too. The name has been changed to crescent university.
Thapar university also accepts JEE main scores for admission. I think they also consider the board exam marks like SASTRA University. so you have chances for admission in that college also.
Dhirubhai Ambani institute also admits through JEE scores and they also consider board exam marks. so that you have good chances of getting admission there also.
All the best!

Well, B.Tech Biotechnology from Thapar is a pretty good option. It is one of the best alternatives for the medical students (who are not going for MBBS) as they have UG, PG and even PhD to offer. They have received NBA Accreditation and the selection procedure is through NEET score. Biotech has more scope in abroad than India. One can actually pursue their career in research. One of my acquaintance had pursued their Masters in Biotech from Thapar University and he is currently in Canada under a research project.
I think you should go with the undergraduate course in Biotech from Thapar University. You will get immense amount of exposure and even multiple career prospects.

Thapar has the legacy of 61 years and it is any day better than the upcoming NITs. Thapar has a well-established curriculum plus they mainly focus on practical learning by providing projects to their students. Moreover, the students undergo rigorous training after their 3 year. The UG program in mechanical is ABET accredited and is specially designed to build a strong base in traditional mechanical engineering. With mechanical engineering, they focus on production designing, manufacturing setups and could implement policies own their own. They are know for their state-of-the -art infrastructure that is the reason they have well-equipped labs with advanced technologies using non-traditional methods. The experienced faculty at Thapar is known for grilling their students thus producing some finest engineers from the campus. In terms of placements, L&T, Mahindra, and Mahindra,Honda Car, HeroMoto Corp ltd are few corporate giants which have visited last year.
You can't expect this kind of exposure in upcoming NIT's. Therefore, if you're ready to sweat out and work in a core field then Thapar is the right place to join.
Good luck!