Assuming it’s the latter as it’d make more sense, you could try this:
This, ideally, should be in the Player blueprint or the Player Controller but can, technically, live anywhere.
Edit: forgot to add that the arrow needs to be in the Absolute Rotation mode:
However, you’ll, most likely, want something with a wee bit more ooomph than an arrow. A spline + spline mesh component could work nicely and can be used to visualise an arc of a lob, for example.