Hey,
LLB or Bachelor of Legislative Law is a three year undergraduate programme. The minimum eligibility criteria is to have a Bachelors degree in any course or stream. After attaining the course,you will be able to enroll as the member of legal fraternity and practice law in India.There is no age bar to pursue this course. You can pursue this course in the colleges like Faculty of Law, University of Delhi ,Banaras Hindu University,Symbiosis Law School Pune.
The fees varies for different institutions. The fee may vary from 25,000 to 2 Lacs per annum.

Hope this helps.
Good luck.