how to allow the player to pick up an object from one location in a level, move it to another location, and drop it there.
You’re looking for an inventory system.
At its very basis, the player character has some kind of system allowing him to store references to objects (could be an array, but a dedicated component would be cleaner). When the item is picked up, you add a reference to the inventory and at the same time deactivate it, so it’s no longer visible, collidable etc. Then when the player drops it, you do the whole thing in reverse: you set its actor location to its new position, remove the reference in the inventory and turn on visibility and collision again.
You’ll also have to add some kind of input to handle picking up and dropping an item, and probably also a way to display which items are currently carried (and from which to select the item the player wants to drop).
It’s a complex task so rather than describe it myself, I searched the web for tutorials. This one looks good and comes in two parts:
I haven’t tried it myself and I don’t know if he updated it after some of the feedback in the comments, but you could give it a try, then ask again if you hit any blockers.