Assignment

Assignment is the process of directly instructing a colonist to perform a specific action. For example, "pick up that pistol" or "haul that corpse".

Assignment is performed by Left Clicking on a colonist, then Right Clicking on the subject of the action, and then Left Clicking on an action from the context menu that should have appeared.

If there is no result from Right Clicking the subject, it probably cannot be directly interacted with. Instead, check that at least one of your colonists has the required Action near the top of their Priority list, using the Overview menu.