My Apple Watch won’t turn on
I charged it and it still won’t come on
Question marked as
An Apple Watch which has been powered down should power up automatically as soon as an active (powered) charging puck is applied to the back of the watch. You should not need to press any buttons. If it doesn't power up at all there is a bigger problem. Either the battery is completely dead and not accepting charge, or the main logic board has failed. I guess it could also be a failed display so you can't actually see what the watch is doing...
I think your only practical solution is to get the watch inspected by Apple Service. Contact Apple Support to start the arrangement.