@scottyboy1875: Can you try unplugging your router at the wall for 30 seconds, then plug it back in and wait for the reset process to complete. Now, head to Settings > Connections > Wi-Fi > On > Select your router from the list of available connections, and fill in the required fields to complete the connection. If the problem persists, please try connecting to another Wi-Fi network, a friend or family members, as this will determine if the issue lies with the Z Fold3, or your home network.
@scottyboy1875: Can you try restarting your Z Fold3 in Safe Mode, as this will disable all third party apps, and help to determine if the problem is stemming from an external source. To enter Safe Mode, press and hold the Power button until the 'Power off' prompt appears on the screen then release > Touch and hold Power off until the 'Safe mode' prompt appears then release > To confirm, tap Safe mode > With Safe Mode enabled, ensure Airplane Mode is turned off.
Now, head to Settings > Connections > Wi-Fi, and attempt to toggle it on. If you're able to toggle on Wi-Fi in Safe Mode then please restart your phone as you would normally, and uninstall any recently added third party apps.