I have tried to install Linux (Elementary OS) on both macOS and Windows; and number one impediment? -- the lack of WiFi.
Of course, there is an official troubleshooting here -- https://help.ubuntu.com/stable/ubuntu-help/net-wireless-troubleshooting.html.en
Immediate connection fix
If you cannot connect to the internet, how are you going to connect to the the internet to find out a solution?
Requirements
- An Android phone
You can use "USB hotspot tethering" on Android phone to connect to the internet.
What to do when you now have a connection
Go to https://help.ubuntu.com/stable/ubuntu-help/net-wireless-troubleshooting.html.en and find out your WiFi driver, and install it.
Well, it depends on your hardware.
In my case, for Windows, it is Realtek RTL8821ce, and the solution on StackOverflow -- https://askubuntu.com/a/1071334
For macOS, it is the matter of activating proprietary Broadcom WiFi driver, and you just need an internet connection...