Above is a great silent video explaining how to create keyboard shortcut commands in all REVIT based products.
Because REVIT does not have a 'command line' or at least one that we can see, Keyboard Shortcuts are a quick way to access the existing Pull Down menu commands.
Have you ever noticed that to the right of some pull down menu commands are two (shortcut) keys that you can type instead of going through the pull down menus.
You do not have to hit enter with REVIT just the 2 characters.
It is user customizable by editing
the KeyboardShortcuts . txt file.