iPhone stuck in setup mode because sim card is still "searching"

I went to the beach the other day with my sister out of town, and mistakenly dropped my iPhone 7 plus in the water. i quickly dried it off with my towel. Everything was going fine until I noticed the screen going in and out. So i then powered off the phone and took my case off of it while I waited till I could get back to my car. The car ride back home was crazy because the phone stayed stuck on the apple logo and at this point i had no way to go online to figure out how to fix it so i just waited till the phone died. When I got home i tried to put it the charger and i noticed it took longer to charge then usual. Tired at this point i feel asleep while the phone “charged” the phone stayed on “1%” the whole night. When i woke up the next morning I tried to use my phone. I also noticed i couldn't do anything with the phone unless i kept it on the charger every time i used it. At this point i noticed that my service was gone and it kept saying “searching”. So i decided to reset the whole phone after i backed my pictures and videos up when i should have just reset the network settings. (At this point its past two days and on the second day i let the phone air dry because i read using rice would be bad).............. (which brings me to my problem)............. As i go in to set the phone back up i get stuck on the “set up manually” part because it can't read my sim card and says “searching” still. To make sure my sim card wasn't damaged i put my card into my brothers phone and all of my unread messages started coming in to his phone. So i know the sim card works its just my phone is battery damaged (i know i can fix because of your website) but i don't know how to fix the sim card problem. I can't get past the setup part to even try to do a battery replacement on my phone. PlEASE HELP i will greatly appreciate your advice.

*That screenshot was before i reset my iphone.