The dust is created with an emitter.
Unreal engine light shines through walls.
Then the effect of light beams is done with a projector with the texture of the window that shines on the particles.
There s a window in a dusty room the sun shines through the window creating light beams in the dust and shining on the wall.
In this guide you will create and light a small apartment using different types of lighting technqiues.
Help how to solve light leaking through the wall.