No Internet Access On New Install

[moosetheory]

Hi all,

I recently installed  OPNSense on a random HP box I had sitting around.
The machine has a built in Broadcom gigabit NIC, and an add-in Realtek gigabit NIC.

The installer ran smoothly, and I went through the basic install in the web GUI. However, I cannot access the internet from the machine.
I pick up an IP address from my cable modem. (I use Spectrum if that matters.) The address looks to be sane, as it is an address Spectrum owns. My desktop receives an address via DHCP from OPNSense, and I can access the web UI from my desktop.
Unfortunately, my desktop could not load any web pages. My first thought, was that DNS was having an issue, but then I realized, I cannot ping Google's DNS server. (8.8.8.8 )
So, I tried using the network diagnostics page in OPNSense's web interface to ping 8.8.8.8, and it cannot communicate with it. DNS resolution from there also fails.
When connected through my router, or plugged directly into my desktop, my internet works fine.

As I am very new to OPNSense, I'm not sure what information would be best to help troubleshoot.

So, the actual question:
Does anyone know of anything I may be missing that would keep my internet from working?
Is there additional information that I need to provide to help resolve the issue?

Thanks