Disable Wi-Fi and Bluetooth on Linux
Ubuntu 20.04
Navigate to:
nano /boot/firmware/usercfg.txt
Add following lines:
[all]
dtoverlay=disable-wifi
dtoverlay=disable-bt
And reboot:
reboot
Raspbian (Buster)
Navigate to:
nano /boot/config.txt
Add following lines:
[all]
dtoverlay=disable-wifi
dtoverlay=disable-bt
And reboot:
reboot