Why is nothing working on my phone after water damage

I would post this as a comment but it exceeds the 1000 character limit.

If you want the data off the phone. Consult someone that offers micro soldering board repairs on iPhone. They are the best chance in getting the phone to work again if you need the data off it. You need to get the phone to boot up properly and work if you want the data off it.

I think the iPhone has been probably been damaged so much after leaving the liquid damage inside the phone instead of opening it and most likely I bet you've tried to charge up the phone causing the phone inside to short circuit more from the corrosion setting in.

No amount of rice will evaporate any liquids inside the phone because the rice is literally outside the phone and not inside it.

A normal repair shop usually only check if it turns on with another screen, battery and charger port most likely it will not since you've put the phone in rice and allow the liquid damage to set inside the phone and damage it more. Oven won't help as the liquid is stuck inside the phone it actually needs to be open and won't remove the corrosion on the board anyway.

I know this is pretty lengthy but I just want to get this out.

Otherwise if you can't get it working your only hope is iTunes or iCloud backups that have been made in the past.