Birth Certificate with unknown father

Hi attorney.. The father of my son's birth certificate is N/A, and he is registered under my surname. There was also no acknowledgement of paternity po when the birth certificate was registered. now, i want to correct it by putting his father's name instead of the N/A, at the same time, to register my son under the surname of his father (who is willing to). by the way, we are not married.

i found this requirements online:
♦ Acknowledgement of Paternity
- Photocopy of child’s birth certificate
- Affidavit of Acknowledgement of Paternity (3 copies)
(For birth certificate wherein the fathers name was not indicated at the time of registration.)
- Three (3) sets blank birth certificate forms (Municipal Form No. 102)
(For birth certificate wherein the fathers name was not indicated at the time of registration.)
- Processing Period - Fifteen (15) working days

if all requirements are secured, does this mean my son will have a new birth certificate reflecting the corrections?

thanks..

no, the registrar will just affix a stamp on his birth certificate that the father issued an ausf