How can I turn off SOS mode on my iPhone?

You don't turn off SOS.

When you have contacted your carrier, and your phone is working with their network again, SOS will no longer appear.

i can not turn off sos

If you see No Service or Searching in the status bar on your iPhone or iPad (Wi-Fi + Cellular), your device isn't connected to a cellular network. If you see SOS or "SOS only" in the status bar, your device can still make emergency calls.

If you see No Service, Searching, or SOS on your iPhone or iPad

Hello Parker734!

You shall find helpful information in this Support Article: If you see No Service, Searching, or SOS on your iPhone or iPad - Apple Support.

Have a nice day, and good luck!