I cannot activate the Ethernet service on my Mac Mini M1

• Mac Mini M1 - 16GB
• macOS 15.3.2

Because of my Mac's apparent inability to detect a local WiFi, I have been trying to link my Mac with a laptop running Linux Mint 22.1, which can use the same WiFi, to act as a router for the Mac. I purchased a USB Ethernet adapter and a brand new 5m Ethernet cable and have connected the two machines.

However, I seem to have configuration problems at both ends. On the Mac, the Ethernet service is constantly showing `Not connected`, and I cannot even remember, at this stage, what the problem on the Linux box was! My main priority, initially, is to get the Mac's Ethernet service to be Active.

If anyone could talk me through what steps to try on the Mac to get it to activate the Ethernet service, that would be great. I did have it showing as connected at one, stage, but, foolishly in retrospect, I sought the help of Google's `Gemini 2.0 Flash Thinking` AI model, and it seemed to lead me in circles until the Ethernet service completely stopped being able to be activated.

This is the current state of play...

Any solution, using either the macOS GUI tools or the macOS CLI would be acceptable 😉