Hi there,

Yes, you can do BA LLB after 12th in commerce, the top college in India which offer BA LLB is NLSIU, Bangalore, it takes admission based on rank in CLAT which is an entrance exam based on which top National Law Universities in India take admission, also there is NLU Delhi which conducts its separate law entrance exam called AILET, the details of both these entrance exams can be accessed here, https://law.careers360.com/articles/clat-syllabus

https://law.careers360.com/exams/ailet