Disabling RaspPI4 onboard wifi on a Supervised true Debian install

Hope to find someone who has already done this.

I want to use a USB wifi antenna instead of onboard wifi because I need to be connected to both lan gateway IP 192.168.2.1 and also to 192.168.0.90 IP address of my whole house generator. I was told it was possible if I disabled the PI’s onboard WIFI and used a USB antenna along with NMTUI. I have full Debian Bullseye installed along with HA Supervisor install

If you know of an alternative way to accomplish this I would appreciate a detailed explanation on how to do it

Thanks, Rich