@Xtreme 

Hello, thanks for asking.

Yes, you need to configure this AX10 to connect to your Singtel modem, before that, please confirm what kind of connection you are using with Singtel, you may just connect the Singtel modem to a computer directly and check how to build up the internet. If the internet is working fine, then you can connect the Singtel modem to the WAN port of the AX10 and login to its web GUI to set up the internet. For more details, please refer to the below setup video:

https://www.tp-link.com/support/setup-video/

But if you still failed, please refer to the troubleshooting suggestions below to check your settings:
https://www.tp-link.com/support/faq/1556/

I hope this helps.