Setting up WIFI on the Rock 4 SE is nice and quick on the Debian images as it comes with the correct libraries installed.
This guide is for people running the Rock 4 SE whilst connected to a screen, keyboard, and mouse. If you are trying to run the board in “Headless” mode, I will hopefully have another tutorial shortly.
This guide assumes you are booted up and logged into Debian and on the desktop.
Open up the Terminal and follow the instructions
sudo su nmcli r wifi on nmcli dev wifi connect "SSID" password "PASSWORD"
Once that is done, you should be connected to your WIFI and ready to go.
If you want to scan for other WIFI hot spots around you, you can run
nmcli dev wifi
This will show a list of all the WIFI signals your Rock can see around you and their details like mode, channel, strength, and security configuration.