Hey,
You can pursue undergraduate law degree through two ways. First is the five year integrated programme that can be done after 12th which includes BA LLB,B.Com LLB or BBA LLB and the other is three years LLB programme that is done after you complete your graduation from any stream.
Once you complete your undergraduate Law course that is LLB you are eligible to do Masters of Law that is LLM which is specialisation in any of the  legal sub streams. But it can be done only after LLB.
Again,it's your call whether you want to do Masters in Law or not as you can work in legal firms after your LLB from good college and on the basis of your performance.
Hope this helps.
Good luck.