How To Enable Function Keys on a Macintosh
By default, the Function keys (the keys starting with "F" along the top of the keyboard) are used for things like volume control and brightness on a Macintosh. In order for them to be used as standard function keys without holding down the Fn key, you can change the setting.
- Under the Apple Menu, open the System Preferences application
- The second row of icons is for hardware related settings. Click the icon called "Keyboard".
- Place a check mark next to "Use all F1, F2, etc. keys as standard function keys".
- Close System Preferences