How to install on phone
How to install ios12 on phone
User profile for user:
Nicholas_B2
User level:
Community Specialist
Hello Iggysrus,
Welcome to the Apple Support Communities. We understand you want to update your iPhone and will do what we can to help.
If you're referring to just installing iOS 12 on a device that has a later version, that would not be possible.
If you want to upgrade to iOS 12, you would need a compatible device which would be listed in the link you posted from.
Enjoy your day.