Do you have a menu like the following one:
MenuBar
|--File
| |
| |-Open
| |-Save
| |-Close
|
|--Preferences
| |
| |-Menu
...
And you would like to have an quick access to Preferences -> Menu?
So, your menu would look like this:
Now if you will press |Ctrl| + |P| you will open the FileMenu.
If you press |Ctrl| + |O| you will call the OpenMenuItem (when first pressed |Ctrl| + |P|)
In other words:
To fast access File --> Open
you will have to hold down |Ctrl| and then press |F|, then |O|.
I hope I understood your question correctly
Greetings,
Thorsten