how to move one half of the pen tool?

There is PEN TOOL in Power Window, how to move ONE HALF OF THE PEN TOOL (not both hands)? IF I press ALT, it allows me to move both the hand, but how can I move only ONE HAND of the PEN TOOL in power window or any selection tools, where there is the pen tool. (e.g in photoshop we can use CNTRL to use one hand)
https://pasteboard.co/JUekWdO.png
https://pasteboard.co/JUekWdO.png