NIT

For your answer, I am attaching the link in which you can find the review and can compare yourself that which one is better for you.
https://www.shiksha.com/btech/resources/reviews/reviews-of-nits-in-india
Basically, all are equally good but there are some NITs which are new so you cannot get good infrastructure. But faculty members are good.
Best of luck.

Yes, sure. The eligibility criteria is a minimum of 75% (overall) in class 12th with PCM as a mandatory subject. Make sure you work hard so that you could qualify with very high marks in your respective category, so you will able to get a good college via JEE mains in one attempt.
Best of luck.

It depends on the NIT or IIIT cut-off ranks for CSE branch. If you are qualified with big margins between your score to cut-off marks then there are high chances of getting the colleges. I am attaching a link in which you can predict the college that you will be getting on the basis of your rank:
https://www.shiksha.com/b-tech/resources/jee-mains-college-predictor
Best of luck.

Hi, Find below the link to Shiksha's the finest college predictor which will help you know various colleges and streams that you may have a chance to fit in:
https://www.shiksha.com/b-tech/resources/jee-mains-college-predictor?utm_source=connect&utm_medium=CR_JEECP&utm_campaign=7489993
Wishing you all the best.

Hi, Find below the link to Shiksha's the finest college predictor which will help you know various colleges and streams that you may have a chance to fit in:
https://www.shiksha.com/b-tech/resources/jee-mains-college-predictor?utm_source=connect&utm_medium=CR_JEECP&utm_campaign=7489993
Wishing you all the best.

Hi, Find below the link to Shiksha's the finest college predictor which will help you know various colleges and streams that you may have a chance to fit in:
https://www.shiksha.com/b-tech/resources/jee-mains-college-predictor?utm_source=connect&utm_medium=CR_JEECP&utm_campaign=7489993
Wishing you all the best.

Hi, Find below the link to Shiksha's the finest college predictor which will help you know various colleges and streams that you may have a chance to fit in:
https://www.shiksha.com/b-tech/resources/jee-mains-college-predictor?utm_source=connect&utm_medium=CR_JEECP&utm_campaign=7489993
Wishing you all the best.

Hi, Find below the link to Shiksha's the finest college predictor which will help you know various colleges and streams that you may have a chance to fit in:
https://www.shiksha.com/b-tech/resources/jee-mains-college-predictor?utm_source=connect&utm_medium=CR_JEECP&utm_campaign=7489993
Wishing you all the best.

See, its completely depends on your rank in JEE Mains. But still you can predict your college by JEE Mains college predictor whose link is as follows-
https://www.shiksha.com/b-tech/resources/jee-mains-college-predictor.