PPPOE and WAN configuration

[mauro]

Dear all,
I have OPNSENSE connected via Ehternet cable to the Modem.

At the moment OPNSense manage the PPPOE connection

My questions are:
1) do I have to assign a network to the interface used between the modem and the FW?
2) which interface should be set as WAN the network to the modem or the actual PPPOE interface?

At the moment I've set the modem - fw network as WAN with related firewall rules but litterally all incoming connections are coming using the PPPOE interface.

Thanks for your advice