Apple watch wont turn on

A cracked screen would certainly compromise the water resistance of your watch. The internal components may be damaged by water intrusion. Generally, water damaged watches are uneconomical to repair. In other words it would cost more to repair than the watch is worth.

If you’re not in a hurry, let the watch dry out for a week or more and then try charging the watch using an Apple cable/puck and wall charger. Monitor the charging to determine if the Watch is getting hot. If watch gets hot, discontinue charging and talk to Apple about repair or replacement.