Solve the iPhone appears support.apple.com/iphone/restore
Solution 1: Use Aisi Assistant.
It may be because the phone has entered the recovery mode.
After the phone is connected to Aisi Assistant on the Mac side, using Aisi Assistant’s "Exit Recovery Mode"
has been tested to be effective
Solution 2: Force restart the iPhone
Force restart the iPhone 8 or iPhone SE (2nd generation)
Press and quickly release the volume up button, press and quickly release the volume down button, then press and hold the side button. When the Apple logo appears, let go of the buttons.
Tested invalid