My phone does not connect to any network help.

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

When done, restart your iPhone then test it.

If you get no help, and if the issue is happening with all WiFi networks, have your device inspected at an Apple Store or Authorized Service PRovider:--> Apple – Location Selector

Regards

Giulio

See these troubleshooting steps. If your iPhone, iPad, or iPod touch won’t connect to a Wi-Fi network - Apple Support