WARNING: This is for advanced users - if you missconfigure your wired network you most likely have to reinstall!
Login to your KiwiSDR via SSH or enter the commands via console in admin section of the webinterface
First we probably need to install firmware and stuff for Wifi dongles:
apt install firmware-realtek firmware-ralink firmware-misc-nonfree wpasupplicant wireless-tools
After that, your device should be recognized automatically - see end of dmesg
output after plugging it in.
(If not - you might have a device which requires compiling a driver, etc. - sorry, not described here.)