Setting up OPnsesne as main router and firewal Home Network

[smnaqvee]

Hi All !

I am trying to shift up exiting AT&T network through OPNsense firewall. I got Lenovo think Center mini with 2 etgernet interfaces and 8Gb RAM and 250GBSSD. I wil luse this to install Opnsense . So existing network is AT&T fiber connected to AT&T router then I have 2 wifi extenders at home. My exiting Promxox attched to one of extenders .

PROMXO runing OPNSense and having 2 interfaces LAN 10.10.10.0/24 and OPT 10.10.20.0/24 . All running fine so far.

Bit confused as I will attach main WAN to newly installed OPNsense machine so what to do with exiting AT&T router then ? But if I discard AT&T router then will have to put new wifi access point on OPnssne LAN port right ?

Kindly review and suggest any best possible solution and guidance.

Regards