Perhaps a desktop icon for Help that sorts before all the apps in the second group and which is a basic cheat-sheet?
Apart from power down, what else would it need to cover? Closing an app? Switching to another app? Opening another app?
At the end of the day, it’s what you are used to - and it takes time. The iPhone still manages to astonish me with obscurity and lack of user-friendliness after so many years.