Can I change my college after B.Com 1st year degree college?

Yes, you can take transfer to another college for the 2nd year in same course you should just apply but there is no guaranty that you will get the transfer.

Yes, you are free to change your college whenever you wish to do so. But here by changing college I mean that you wish to drop and then do your Bachelor's from somewhere else, because there is no such provision of exchange programme. But before doing so think twice because it can be tough to secure