How to get my iPhone working again since it has water damage?

Water Damage is not covered by standard warranty. 💦

However, AppleCare+ can help.

Turning on a wet machine can cause more damage and increase the cost of repair. ⚠️

Based on your situation, I recommend service.

Service Checklist:

• iPhone service pricing.
• Check AppleCare Coverage.
• Get your iPhone ready for service.

Click ▶︎ Start a Service Request. ⚛️

Need more help?

• Chat now or call 1-800-APLCARE.
• International Support.

Click ▶︎ Check Repair Status. 🔧

Hello,

If you have a case on it remove it and let everything dry out in the air for a few days. Then, it may work for awhile. However, it will probably never work completely well again. See this for detail:

About splash, water, and dust resistance of iPhone 7 and later 

Water and other liquid damage to iPhone or iPod isn't covered by warranty 

Good luck.

Liquid damage is not repairable. The phone will have to be replaced.