It totally depends on the scheme of college you are talking about. Most colleges provide the stream change system after first year provided you dont have any backlogs in first year. Some colleges also let you change your stream after 6 months that is first sem. Your CGPA also matters in some college to do the task of change. Keep in mind to maintain a good CG.

Hello aspirant.

As per your query.you want to change a branch ECE TO CSE.yes it is possibe after one year.for branch change you have to score minimum 8.5 cgpa.and you have to come under top 10 rank in class .after that you have to apply for it .if is there any vacent seat are availabe in  cse branch.then you will change branch.

Thanku