Visible rays of light

I’m creating a low poly scene with a guy sitting at a computer and i want the computer screen to be illuminating him and the desk with a “shaft” of visible light in the air (like how you can see sun rays through a window) How would i achieve that effect? Screen Shot 2020-02-04 at 7.46.43 PM|609x499

Hi, this tutorial might help: https://www.youtube.com/watch?v=EXiZoT_5SHs