iPad won't turn on after getting wet

Water and electronics do not make happy bedfellows. Your iPad is not designed to be water resistant. While it may survive being splashed with water if immediately dried, it will almost certainly suffer irreparable damage if allowed to get wet or is submerged.

You would be best advised to take your iPad along to the Genius Bar at your local Apple Store or Apple Authorised Service Provider (AASP) - where the technicians will be able to assess your iPad. If repair isn’t possible, the iPad can be responsibly recycled - and you’ll be in the best possible place to explore possible replacement:

Genius Bar Reservation and Apple Support Options - Apple

Wait several days for it to dry out. If it still won’t turn on make a genius bar appointment to find out what Apple can do for your dead iPad→Genius Bar Reservation and Apple Support Options - Apple