No,you can not change your branch in first year but you can change your branch in second year though.Most colleges allow it.It depends on two factors.

Firstly,College fixes a thresold CGPA or percentage.Your CGPA have to be higher than the one set by the college.

Secondly,it depends on the nunber of seats college have that in particular branch.

For e.g.If minimum thresold cutoff is 8 CGPA and you secured exactly 8 then you are eligible to change the branch but if a college have suppose 80 seats in CSE and 72 get into admission  in 1st year..imagine people like you who have in their mind to change the branch in second year also filled the form and lets suppose 16 people also filled the form and 8 of them secured pointer greater than 8,then definitely they getting the seat in CSE and not you.I hope you understand what i mean.

There is a criterion of branch change in almost every college. To change your branch you must score the minimum CGPA as fixed by the institute. Every branch has its own minimum CGPA reqirement, you can contact your college academics to get the detailed information.