Address proof regarding

The Electricity Bill is in whose name ???

All property documents including electricity bills are still in father name

It is advisable to change the name in the Electricity Bill since continuing the name of a deceased consumer is not a legal practice. You can change it to your name or in the name of Spouse ( your Mother's name ) and take a No Objection Certificate ( NOC ) from your Mother and provide the same in the GST Registration application...

This is my personal advise. Also consult with other members of the forum for better suggestions...

Regards,
Shivam RC.

Thank you

Your most Welcome Sir...