Hey, to be admitted in JNU you will have to first fill up the application form from their official website which will be released in the month of April. There are some eligibility criteria like your marks. You will have to get at least 50% or so in your bachelors to be applicable to apply. Then you will have to sit for the entrance exam held by the university and if you are selected you will be admitted to the university. I hope this helped.

Best wishes.