Using RPI4 as firewall

HI

I have a rpi4 which I was using for various things and have decided it could be fun to use it as a firewalll.

I would need a total of 3 ethernet ports and have found some Dual Gigabit boards but these are for the compute module.

My question are they compatible with the rpi4?

Guess my other options would be USB adapters

Any help would be greatly appreciated.

What is your current setup?
Are you using WIFI?
If you already have a router in use, just put the Pi between it and you WAN connection.
Do that and you only need one more Ethernet plug.
Internet / WAN > Pi firewall > router or ethernet hub.
Disclaimer, I am not a network expert.

Currently using a watch guard solution but was considering moving away from that would be looking to have 2 wan connections and 1 lan connection.

I can do the wlan stuff, that’s nice and easy but would prefer to use hat based Ethernet rather than usb.