Wifi can’t stay connected longer than an hour on Big Sur

I have a 2011 iMac on Big Sur, I can’t stay connected to wifi for longer than an hour. Firefox tabs often crash, wifi disconnects and the whole computer eventually locks up and throws a hissy fit until I need to unplug it to force reboot.

Any ideas on what could be causing this? I need this iMac for school work and I had to miss an online class because of this. No I cannot ask my school for a new one as it’s a BYOD

Author: @VLCInsanityPlayer