After your graduation, you are eligible for 3 year LLB. The criteria varies in all colleges. The 3 year exams for law studies are:

• DU LLB
• BHU LLB
• LSAT India
• PU LLB and more

In general, you need to have 50% minimum (general category) in your graduation to apply for 3 year law exams but refer to the above exams official site for apt information or you can even ask here for whicn exam specifically you are asking for.

Based on your entrance and score you get shortlisted for the selection in that college.

The forms will be available from Feb 2018 for most of the exams. Till then you can focus on the preparation as well.

Good Luck.