Wifi Not Working KDE Neon Troubleshooting Guide

Installing Driver

3. 3. Installing Wifi Driver

   How to Install Wireless Driver in KDE Neon

   Wifi Driver KDE Neon Setup Guide

   GNU/Linux KDE Neon Wifi Driver Installation Tutorial

   And then in case of further Trouble you should also try to see: How to Update Firmware Guide.
   Last, you have to know how a Possible Turn around is of Buying some Cheap USB Wireless Dongle.