Question [Animation Rigging] How to move a rig except for certain bones?

I am trying to create a dynamic climbing system where the player can move the hands with the mouse.

I have a humanoid rig and I want to first have only the hand move, and then the entire rig move towards that hand, but the hand should stay where it is. But when I move the rig towards the hand, the hand moves with the rig.

Do I need a workaround, or is there some clean solution for this. I was thinking about ordering constraints in the hierarchy, but I don't know anything else.