Well, I m a commerce student in class 12th, can you suggest top 5 colleges for bba llb or bcom llb? Any yes can we do BA after 12th commerce?

Yes you can do BA LLB no matter from which stream you are. Most top colleges like NALSAR, NLS Bangalore etc offer only BA LLB so you can go for these without any problem.
But if you're looking for colleges offering BBA/BCOM LLB these are GNLU Gandhinagar, TNNLS Trichy, Symbiosis Pune, Jindal Global Law School, Indraprastha Uni, Delhi Panjab University,Chandigarh, Christ Uni etc.