For B.tech CSE branch to take admision in top colleges you have to prepare for JEE Exam.
Below are the top exam for engineering admission (2017)
1- JEE Main
2- JEE Advanced
3- BITSAT
4- VIT
5- SRM
6- Amrita
7- Manipal
You can also apper in your state level exam.
To know in detail about the exam you can refer below link
List of Engineering Exams
Good Luck!!
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