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Pressing function and numeric keypad keys
To press a function key (F1 to F12), say "Press Function" and then the name of the key. For example, say "Press Function 1" to bring up the online Help. To press the keys on the numeric keypad, say "Press Keypad" and then the name of the key. For example, you can say "Press Keypad Minus" to press the keyboard shortcut that opens the Correction menu. See the complete list below:
i am only going to list the one you are interested in, which means, you would have to say:
Keypad Enter
Note:
Num Lock must be on for the "Press Keypad" commands to work. You can say "Press Num Lock" to turn Num Lock on.