It's shitty that they make you do this, but you can actually install windows fine without a network connection by using Shift+F10 to open a command prompt during the startup flow, then typing oobe\bypassnro, which will restart the startup flow with a new option to setup without wifi.
It's shitty that they make you do this, but you can actually install windows fine without a network connection by using Shift+F10 to open a command prompt during the startup flow, then typing
oobe\bypassnro
, which will restart the startup flow with a new option to setup without wifi.