Hello aspirant,
I am here for helping you.
As per your question I want to tell you for getting admission Engineering colleges for CSE branch you will have to first clear national/state/university level entrance exam so that you could take admission in good colleges and you can also take admission in some colleges with your class 12th marks and for many colleges you must score at least 75 percentage in aggregate subject of your class 12 and for some colleges it may be 50 percentage only.
I am providing you a link below where you can see the list of engineering colleges in India for CS:
https://engineering.careers360.com/colleges/list-of-computer-science-engineering-colleges-in-india
I hope it will help you........
For more queries you can upvote me and can ask in the comment box.
Best of luck.