SRM Institute of Science and Technology, Kattankulathur

It's an average college. The placements are neither very good nor too bad.

VIT is very industry oriented! They'll make sure u get into the industry and so they train you accordingly! And their curriculum is tightly monitored by industrial experts!

You can download it from the NET. There you can get the papers with the key.
From this link you can download the paper.
Link: http://www.10yearsquestionpaper.com/2017/01/srm-sample-question-paper-entrance-exam.html?m=1.

For pursuing B.Sc in CS/IT you need science stream in your 12th without it you are not eligible for B.Sc because B.Sc CS includes maths, computer and physics as main subjects.

Yes, you are eligible.
The eligibility is Bachelors degree in Information Technology/Computer Science/ Physics/ Statistics /Electronics or equivalent examination with at least 45% marks in aggregate from a recognized university.
B.Tech./BE degree holders in Computer Science/Informational Technology are also eligible for M.Sc. IT course.

No, SRM doesn't conduct separate entrance exam for admission in BA LLB.

No, SRM University doesn't conduct entrance exam for BCA. You will have to fill the form which is available in SRM website.

Not the best. India has many institutions that have a good name and cannot be compared with each other. If SRM is falling in your criteria of best then it must be opted by you. it has a good brand name. Do some research on the placement and public notion around you.

SRM conducts it's own entrance exams every year. You have to fill that and qualify exam to get in. Take a look here: https://www.shiksha.com/university/srm-university-chennai-kattankulathur-campus/exams/srmjeee-ug.

Yes, you can, but you need to start from the first semester.