Which one of the obc-ncl certificate is required for jee, state government certificate or central government certificate?

You should have the certificate given by the central government only as it is conducted by the central government under guidance of it so you have to submit those only and you have to submit them even while application submission also , so all The best for your future

Dear Madhusudan Kumar

• It depends on the institute to which you are applying for admission.If you are applying for IITs, NITs, IIITs ( except IIITH ) and CFTIs through your jee score then you required certificate issued by central government.While if you are applying for colleges like DTU,NSIT you need the certificate issued by state government.
• Caste certificate is considerd valid for 6 months only.So apply for certificate atleast 4 weeks prior to it's need,to prevent yourself from last time rush.