Question about adding additional WiFi network via USB

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Are there any good tutorials out there about adding USB WiFi devices on Opnsense?

I keep running into problems where enabling a USB WiFi causes all DNS and DHCP to break on my wired networks.

Here's what I'm trying to do:
Add a USB WiFi device to my Opnsense box to run a dedicated guest WiFi network separate from my main wired and wireless network.