Hi

NTSE is a national exam for which caste certificate is mandatory to avail any benefit.

SC caste certificate is valid for three years. Make sure your caste certificate is as new as possible. State issued certificate will do provided it is translated in English if it is in your state language. There is only sperate state and central list for obc category so only obc needs to provide with a central issued certificate. In your case state issued certificate in a proper official format will do.

State wise lists of SC

https://socialjustice.nic.in/UserView/index?mid=76750

Hope this answers your query!