Welcome to the Community @thangvan
Note: The bundled VoIP phone will not work on a third party modem/router.
To set up your TP-Link AC1200 modem/router for your TPG FTTN service, you may follow the steps here: Fibre to the Node/Building (NBN FTTN/FTTB) Setup Guide
Once you are done with the physical setup, you may configure the modem/router by using the article that we've created as a guide : How to set up your TP-Link VR1600v modem
Feel free to search Community for help with your issue, or contact us and we'd be glad to assist you.