Hii

Yes ofcourse you can go for BA LLB after studying PCMB in class 12th.
The eligibility for BA LLB is that you must have qualified your class 12th with minimum 50% marks. No specific subject is mentioned.
You can simply appear for the respective entrance exams and after qualifying it you can easily get admission in BA LLB cousre.
For All the NLUs you will have to appear in CLAT exam and for NLU delhi you will be required to appear for AILET exam. There are many more exams also on university level.

Thanks!