No, computer science is not compulsory to complete your B.E or B.Tech.
You can choose other branches as well as per your interest.

Below are the branches which you can choose

1- Civil Engineering
3- Chemical Engineering
4- Mechanical Engineering
5- Electrical Engineering
6- Aerospace Engineering
7- Metallurgical and Materials Engineering
8--ECE
9- Mining Engineering

HI, Computer science is a branch in Engineering and you can pursue B.Tech in these branches. Also some other branches are:
Chemical Engineering
Computer Science
Civil Engineering
Electronics engineering
Information Technology
Mechanical Engineering
There are many.
You can choose any you seek your career in.
All the best.