iPhone SE 3rd gen has a screen with large letters and is frozen
The screen is frozen and won't turn off no matter how long I hold down the side button. This phone is fully charged.
iPhone SE, iOS 17
Question marked as
Holding just the power button will not power off your iPhone. You hold the volume up and power buttons at the same time to power down an iPhone.
In your case however, try a Forced Restart --> Force restart iPhone - Apple Support (CA)