No WiFi networks listed in WiFi menu

You can try Option-Click on the WiFi icon at the top right and select Open Wireless Diagnostics. Run it.

Use Wireless Diagnostics on your Mac - Apple Support

Another thing to look at is Apple Menu > About this Mac > System Report > Network > WiFi. What do you see?

If the WiFi icon is still active it may not be a hardware issue but we cannot be sure.

Just in case, check if the WiFi router is not configurer for MAC address filtering or something like that.

WD

Simon S wrote:

Sounds like a hardwire issue? Any other things to try first?

in the end it was a loose wifi antenna cable- had to go back to where the screen had been replaced and they admitted it was a problem with the fitting. thank you for your suggestions.

And this you decided not to mention in the original post...

>System Preferences>Networks Do you have any Networks set up here?

Create a new network - Apple Support