Unable connect to WiFi & Bluetooth

Try this procedure:

Settings>General>Reset>Reset Network Settings, keeping in mind that it also resets Wi-Fi networks and passwords, cellular settings, and VPN and APN settings that you've used before, but NO other data is affected.

When done, restart your iphone and test it.

If you get no help, it could be a hardware failure (antenna?). Make an appointment at an Apple Store or Authorized Service Provider and have your device inspected: Apple – Location Selector

Regards

Giulio