If you want an iPhone to appear as brand new from a software standpoint, you need to reset the device to it’s factory settings
After you have reset the iPhone, it will reboot as if it was brand new and go through the standard new setup procedure that all new iOS devices go through, and can then either be set up as new or restored from a backup.
iPhone X / XS / XS Max / XR , iPhone 8 / 8 Plus, iPhone 7 / 7 Plus ,iPhone SE, iPhone 6 / 6 Plus / 6s / 6s Plus, iPhone 5 / 5c / 5s and iPhone 4 / 4s
How to restore default iPhone settings without erasing content restore default iPhone settings without erasing content
Open Settings, swipe down and tap General
Swipe to the bottom and choose Reset
To restore all settings to the default without deleting your content, tap Reset All Settings (note this does remove Apple Pay cards) tap Reset All Settings again
To restore a particular default, choose Reset Network Settings, Reset Home ScreenLayout, etc.