Hey!

You query is not as much clear, so the answer given below is generelised.

Caste certificate is mandatory for the candidates who wish to join any institute by their category rank or score. Their are different categories such as SC, St, pwd, ews and obc. And for same purpose , a caste certificate is prepared by the government which is valid for an year. so, if you are from obc category and wish to get into some institute with same then you must have your caste certificate.

Thankyou.