Hey Arun.

Yes, CLAT entrance test is conducted for admission in the course of LLM for admission in various National law Universities of India. The eligibility criteria to take the test is a minimum aggregate of 55% in your law degree for the general category. 

For admission in colleges other than the NLUs separate self conducted entrances or admission procedure is laid out as CLAT is for admission in ony NLUs.

You can use the link below for more details.

https://law.careers360.com/exams/clat-pg

Best of luck