Hi Bharath,
Yes, you can change your engineering branch in MIT, Manipal even if you are taking admission in the year 2020. But remember there will be very much competition for changing branch specially to CSE.
Branch changing depends on a lot of factors like :
Refer here for more info - https://www.careers360.com/colleges/manipal-institute-of-technology-manipal
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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