Here is my light beam:
What I need to know is how I might go about adding light to this as if it were a sunlight beam that is being bounced off mirrors to say light a room amoung other uses. Any help would be greatly appreciated.
if you were using 4.20 you could probably stretch a rect light across it. since you are using 4.17 you could try adding pointlights to wherever your laser hits a wall.
Are you looking for something like global illumination?
If yes ,this might help you : Light Propagation Volumes | Unreal Engine Documentation
Also this topic might help : Secondary bounce light from flashlight possible? - Rendering - Unreal Engine Forums