JEE

As per, Eligibility Criteria (Qualifying Exam) Pass with 60% aggregate marks in 10+2 (with Physics Mathematics, Chemistry and English or equivalent, subject to qualifying LPU NEST. You should apply for LPU NEST exam. The highest Package Availed by Engineering (CSE) Student The highest package offer

Top CSE colleges in India
IIT Bombay - Indian Institute of Technology. Lovely Professional University, Phagwara
MIT Manipal - Manipal Institute of Technology. COEP Pune - College of Engineering. VIT Vellore - Vellore Institute of Technology. SRM University Chennai - SRM Institute of Science and Techno

Yes, you have a pretty good chance to get into Lucknow with a 89 percentile.

https://www.shiksha.com/engineering/jee-main-exam
You will find all the true and authentic information about your college here.

Firstly VIT admission is based on viteee entrance exam. So you need to apply for the exam and do well in the entrance exam. After that based rank you got in entrance exam admission is taken . The only way to get admission to VIT is through entrance exam only not with JEE rank. But they will consider

To get a free seat in Gitam college you need to rank in JEE Mains 1-5 and their GAT exam 1st rank.

Yes, if JEE Mains score is low there is a chance of getting NIT through home state quota. Also for precise answer visit Shiksha college predictor. https://www.shiksha.com/college-predictor.

You can refer to the link given below-https://www.shiksha.com/university/vellore-institute-of-technology-vellore-29714.

No, I think it might not possible.