The only thing you can do with any phone is press home button and power button hold for 20 seconds and then it will turn black and then after it turns black it means it will work fine but if it doesn't just restart it and hopefully it will be fine or try plugging in the phone.
Solution #1: Plug the phone in
Solution #2: Put the phone in dry uncooked rice
Solution #3: Get a refund where you bought it but have a receipt for it if the store gives refund or coverage of phone damage
Solution #3: Sell it at a cellular device store they might repair it and sell it for exchange of money or another phone
Solution #4: Leave it in the sun for at least 24 hours at least or overnight
Solution #5: restart the whole phone