Open Settings
Tap Wi-Fi
Tap the connected network or the network name
Tap Password
Authenticate with Face ID, Touch ID, or passcode
View or copy the Wi-Fi password
If you are sharing the password, bring the other iPhone close
Make sure Wi-Fi and Bluetooth are turned on
Unlock both devices
Tap Share Password when prompted
If you use iCloud Keychain on a Mac
Open Keychain Access
Search for the Wi-Fi network name
Open the saved network entry
Check Show password
Authenticate with your Mac password or Touch ID