CGPA is not the primary criteria for branch migration but scoring well in CSE subjects is(or whatever branch you want to migrate)
For migration in CSE branch kn VIT you have to compulsorily enrol in 2 courses those are, Data Structures and Algorithms and Digital Logic Design(course code of CSE). Similarly you can get info about which subjects to take for other branches in which you wanna apply to. Now you have to score well in these (minimum of A grade for that matter) and you current CGPA is already very decent in order get the migration.
I would like to give you a suggestion that you must and must enrol for those courses in FFCS otherwise you won’t be able to migrate and again CGPA is not the primary criteria for branch migration.