Performing a force restart won’t delete any data, but can be helpful if your iPhone 11 is frozen, won’t turn on, or needs troubleshooting.
Step 1 How to Force Restart an iPhone 11
Quickly press and release the Volume Up button (1).
Quickly press and release the Volume Down button (2).
Finally, press and hold the side button (3) until the Apple logo appears, and then release.
The screen will temporarily go dark as the iPhone shuts down and reboots. Keep holding the button until you see the logo.