How to fix iPhone (that was dropped in water)?

It turns on by itself sometimes but ////I always try turning it off (power button and home button pressed together). When it's on the screen is black besides some colored vertical lines (the colors vary but they re the colors of my lock screen background). I can't really access it at all since I can't even see the passcode screen or time/date. The back camera looks a bit fogged up. I was at work and had no rice and it's been a few hours. It's in rice now but I'm wondering if it's worth it or if I should just take it to the apple store (hoe much would it cost?). Any help would be appreciated.

Oh my goodness so many errors… Well for starters I meant how not hoe sorry

Take out the screws in the bottom, slide off the back plate, let sit in a bowl of rice for a couple hours to help pull out the moisture, disconnect and replace the battery.

Start it in 24/48 hours if it's still acting up, it needs replaced.

Use a substance with a high affinity for drawing out moisture. An inexpensive option is to place the phone in a bowl or bag of uncooked rice overnight, Rice Krispie cereal, or just cover the phone in paper towels. The rice might absorb some remaining moisture
If available, it is preferable to use a desiccant instead. Desiccants may absorb moisture better than rice. You can also try slipping the cell phone inside a plastic bag that can be sealed or a plastic container (airtight). Add a desiccant packet, such as silica gel - often found with new shoes, purses, noodle packets, etc - in with the cell phone. The downside of this method is the packets packed with shoes has usually already reached its absorption capacity. Desiccants for flower drying can usually be purchased at most craft stores. Leave the phone with the desiccant or rice as long as possible (at least overnight) to absorb the moisture.
Rotate the phone to a different position every hour until you go to sleep. This will allow any water left inside to run down and hopefully find an opening to escape.