Help please: Displaying health bars

Hey all, working on a project here and trying to make a boss encounter. I was thinking about putting a health bar across the top of the boss mob so the player can see the health bar of the enemy while they fight. I'm not finding any ways to do this implemented currently in the engine or in the forum. I was just wondering if anyone might have any ways they know of to do this? Or even a health number above their head would work I suppose, but a health bar would be ideal.
Thanks for any help.