Hi,
Any student who have minimum percentage of marks in the qualifying examination (i.e., 10+2), can take part in CLAT.

If candidate belongs to Unreserved/OBC/Specially Abled Persons (SAP) and other categories then his 10+2 marks must not be less than 45%

In case of candidates belonging to Scheduled Caste/Scheduled Tribe (SC/ST) categories then his/her 10+2 marks must not be less than 40%

As of now, there is no Age bar for CLAT.

CLAT 2019 - Preparation Tips, Syllabus and Best Books

Best of luck!