Uttar Pradesh

IIMT-Noida is a better option, for details check out the college reviews below:
https://www.shiksha.com/college/iimt-group-of-colleges-greater-Noida-3248/reviews
https://www.shiksha.com/university/iimt-university-Meerut-3238/reviews.

It's better to search in online.

Migration certificate is only needed if you seek admission into any other university, whether it is in your home state or in other. You will get it by the university from which you complete your course. Migration certificate is also sought after clearing 12th class at the time of admission to any course. That one is provided by the school.

No there is no such type of entry.

KNIT, Sultanpur is a better choice, as it is more focused on placements and academics compared to BIET.

Yes, you have a good chance of getting CSJM University, Kanpur. But I'm not sure about the branch you will get there.
One thing I want to suggest you is- go for every round of counselling process. This will help you to get a better college.

It's difficult to say about that. But if I were at your place I will go for BIET Jhansi because REC Banda is not good college. REC is preparing himself to get better from last year.

As per my knowledge, PSIT is better out of the mentioned colleges for CSE. Placements & academic record of PSIT are far better than those of the above-mentioned colleges. Recently, I have come to know that Infosys recruited 154 students from PSIT, which was the highest in terms of numbers in UP. As far as academics are concerned, I could find PSIT among the top-three colleges in AKTU.