After restarting Fallout 4 pressing the equivalent button from above will open the console. Should this for some reason not work, you can always set your keyboard's language layout to US in the Windows control panel. It cannot be used in the game console versions or in Survival mode. It is useful for altering content while in-game, but may be used to cheat as well.
The console is a debugging tool in the Windows version of Fallout 4.
