n macOS, what launch point provides access to almost all the settings needed to administer a macOS system?

System preferences.

Explanation:

MacOS is the primary operating system designed and developed for Apple computers (MacBook).

In macOS, system preferences is a launch point that provides access to almost all the settings needed to administer a macOS system. The system preferences allow users to change various settings on their Mac computers such as changing the desktop layout, desktop picture (wallpaper), size and location of the dock, font size, appearance, energy saver etc.

to change your username, you must:

1) make sure what the username you want to change to is allowed in this community

2) contact a administrator (for example, jaysl)

3) through pm, tell the admin what you want to change to

4) if the username is allowed, it will be changed in a matter of seconds (minutes at most)

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