To add NFC to bangle js same as in puck

any GPIO's exposed on bangle js to add nfc antenna or chip?

No - they're literally all used: https://www.espruino.com/Bangle.js+Technical

Also only D9/10 can be used for NFC, and they are definitely in use as I said above.

I see SOC nRF52832 has support of NFC, can i activate NFC radio or emulate it without antenna?

No - doing so would disable D9/D10 which would stop the LCD working

where is the NFC antenna in the puckjs is it along with nrf SOC or where it embedded in puckjs?

It's buried inside the PCB, right around the edge.