my phone is frozen and I cannot turn it off

The method I posted previously should force a restart under any circumstances, doing this cuts power to the logic board of your device for a split second. If even that doesn't work, you have a much bigger problem. Try that method again, and if that doesn't work, contact Apple's own support team at support.apple.com. You will need to hold the side button until the Apple logo appears. After that immediately release the button.

Press and quickly release the volume up button, press and quickly release the volume down button, then press and hold the side button.

That does not work (trying to turn the phone off), and all the apps don't work. I can't get into settings to force a shutdown.