Hi Sritam,
Yes, you can change your engineering branch from Mechanical to CSE if branch change procedure is going on in your college now. Please note that you should be in 3rd Sem now. But remember there will be very much competition for changing branch specially to CSE because a lot of students will be trying for that.
Branch changing depends on numerous of factors like :
Refer here for more info - https://engineering.careers360.com/articles/top-engineering-branches-in-india
To know your other best admission possibilities of Institutes & branches in JOSSA & State counseling as per your percentile, You can use JEE Main College Predictor tool given below
https://engineering.careers360.com/jee-main-college-predictor?icn=QnA&ici=qna_answer
Feel free to ask doubts in the Comment Section.
I hope this information helps you.
Good Luck!
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