I'm now appearing for my school's final years examination, and it's time for me to decide the branch for my graduation.
So, I'm now stuck between choosing Computer Science Or Mechanical Engineering? because I'm interested in both.
So, please give me some suggestions which branch should I choose.
We can't really offer any advice. Those are both very different fields, but both are respectable. It boils down to what interests you more, what pays more on average (if that's important to you), quality of work, work-life balance, etc.
Really you should have done this sort of research long before your time to decide.