Changing arrow direction in procedures?

So, I have an item that shoots arrows when it’s used (not a gun, but just a plain item with a procedure that does that). I know how to make it shoot forward and backward (positive and negative values for the speed), but I’m trying to get the arrows to shoot to the left or right of the player, and I can’t figure out how. I don’t even know if there is a way to do this, but it seems like it would be possible.