Hey there, and welcome to Apple Support Communities, SimonHill100!
From our understanding, your iPhone 11 isn’t connecting to your cellular network, Wi-Fi, or Bluetooth. We’d be happy to help out!
Since you mentioned that you’re unable to update your device, we’d recommend following the steps listed here first: If you see an error when you update or restore your iPhone, iPad, or iPod - Apple Support
Next, If your computer doesn't recognize your iPhone, iPad, or iPod - Apple Support has some great steps if your computer isn’t recognizing the iPhone.
Lastly, if the steps above don’t help, follow the steps under “If your device turns on but gets stuck during startup” at: If your iPhone, iPad, or iPod touch won't turn on or is frozen - Apple Support
If you're still experiencing the behavior after following all these steps, let us know exactly what you are experiencing. For example, do you see "No Service" or are you unable to connect to cellular data? With Wi-Fi and Bluetooth, are you connected, but have no connectivity, or are they greyed out in Settings?
We hope that helps, and cheers!