My son's iPhone 8 is stuck with the apple logo on the screen

If your iPhone, iPad, or iPod touch won‘t turn on - https://support.apple.com/HT201412 - Your iPhone, iPad, or iPod touch may occasionally stop responding to buttons, switches, or touchscreen input and may exhibit one or more of these symptoms:

Does not return to the Home screen after you press the Home button;

Does not wake from sleep after you press the Sleep/Wake button;

Does not turn on (or power on) when you press any button;

Does not start up past Apple logo;

Appears frozen or unresponsive;

Is unable to "Slide to Unlock" or "Slide to Power Off";

Hi

Try a reboot press side volume up button quick then the side volume down button quick then hold just the power button down until you see apple logo this can take 30 seconds.

Cheers

Brian 🇬-1F1E7;