my iphone 14 pro won't even turn on

Force-restart your phone

• Press and quickly release VOLUME UP

     then

• Press and quickly release VOLUME DOWN

     then

• Hold the SIDE button until an Apple logo appears (15-30 seconds), ignoring "slide to power off" if it appears

The operative word here is QUICKLY; and try it a couple of times, the timing is a little tricky.

If you have followed the sequence carefully and it doesn’t restart your phone has a hardware problem. Contact Apple using the Support link at the top or bottom of this page.

Thank you this worked perfectly for me exact same situation.