If your iPhone, iPad, or iPod touch won’t turn on or is frozen.
Try to put your phone in Recovery Mode...⬇︎⬇︎ full instructions in the link above...⬆︎⬆︎
Short instructions...⬇︎⬇︎
Connect your device to a computer. On a Mac with macOS Catalina 10.15, open Finder. On a Mac with macOS Mojave 10.14 or earlier, or on a PC, open iTunes.
Press and hold the Top (or Side) and Volume Down buttons at the same time. Keep holding them until you see the recovery mode screen.
It may take a few tries to get into Recovery Mode but when you do then the phone will be recognized...