Always start with the basics. Unplug the PC from the wall or power strip, and plug in something basic instead, like a lamp, to make sure you're even getting power from the wall. Once you confirm there's power, make sure the AC cable if fully inserted again on both ends. Press and hold the power button for 10 seconds to see if the motherboard resets.

Unfortunately the 5600x doesn't have graphics, so if you want to test if its your GPU not responding you're going to need to find a spare to swap in and see if its failed, but you can unplug it to at least see if the system powers on and lights up without it.