If your wifi was disabled via the kill switch when you installed and configured Qubes, it is possible that your sys-net VM was not assigned the wi-fi PCI device, causing this issue.
If that is the problem, you can fix this by:
- reboot your L14 with the kill switch on (wifi enabled)
- shut down sys-net
- go into the VM settings for sys-net, in the devices tab, and manually add the wifi device (should be 01:00.0 Network controller)
Edit: after doing so, sys-net may fail to start if you turn your L14 on with the kill switch off. For a fix, check my solution here Qubes fails to start sys-net if wifi kill switch is off - #10 by dpr