Power of attorney for nris

Hi, I am USA based NRI. I am planning to purchase a property in india through a home loan from HDFC bank. I want to give my father the power of attorney to purchase on my behalf. I got a format from the HDFC bank.

What should I do next?

Do I need to get the POA notarized from Notary public or getting attested from Indian embassy in USA is mandatory ? US embassy is very far from my place so can I send POA by post or do I need to visit the embassy personally?

Thanks in Advance