When I press the Function keys (F1-F19) nothing happens. How do I use the Function keys?

By default, macOS uses the F keys to control items such as volume and brightness. To use an F key for a game command hold down the fn key, then press the F key you wish to use.

To automatically enable the F keys, follow these steps (depending on the version of macOS you are running):

1. Open System Settings ( Menu → System Settings).

2. Click on Keyboard.

3. Select the Keyboard Shortcuts button (macOS Ventura).

4. Click on Function Keys (macOS Ventura).

5. Turn on Use F1, F2, etc. keys as standard function keys.

The F keys will now work without using the fn key.