That won't do what you want. All it will do is add a KB shortcut to perform a menu selection inside an app. For example, you can setup a KB shortcut of F5 to "Flip Vertical" in Preview so when you have a photo open in Preview and hit F5 the photo flips over. The KB shortcut area you are in cannot be used to launch apps.
You will need some sort of aftermarket app to add this functionality.
I use and would suggest
Alfred. It is a nice launcher and if you pay for their
"Powerpack" it allows global hotkeys that you can configure however you want. You could easily setup a hotkey to launch Calculator.