Have you pressed a function key and it hasn’t done quite what you expected? It is no problem because, as with previous iterations of the Mac operating system, it is easy to alter how they work in Catalina.
Function Keys in Catalina
To change the settings corresponding to your Function keys, go to System Preferences > Keyboard > Keyboard. At the bottom is an option to “Use F1, F2, etc as standard function keys.” Ticking the box next to that option means you then have to press the Fn key alongside that key, to make it perform its special function on the top of it. This includes things like changing your computer’s volume or the display’s brightness.
You can set what the function keys do via System Preferences > Keyboard > Shortcuts. In the example below, pressing F11 or Fn+F11, depending on the setting outlined above, pushes open windows away and shows my desktop.