Ah sorry.
I haven’t done any HUD work yet so I may not be much help.
I don’t think there is a single answer to your question. You could do it a handful of ways.
Anything not in the HUD will basically require you to tether(as a component or otherwise… not sure if component rotation works separately from the root, but either way) it to the player/camera, and then set it’s rotation based on player location, arrow location, and the target location. You could have a simple static mesh as your arrow, maybe even a floating decal?
Then there is the HUD option. I don’t know how to draw the arrow in the HUD, but the rotation calculations should be the same for both methods.