First off you probably want Prop_static Lights because it looks stupid unless they are coming from somewhere, a good prop_static gets rid of this problem. A good way to find one is simply search “light” in the model selecting GUI.
Place and aim the light_spot where you want it, in our case it is aiming directly down and placed right underneath the chosen model. Be careful not to let the origin of the entity (small cross in middle of 2d view) intersect with any geometry or it will not work correctly.
Change the beam angles; there are two to change, the inner (bright) and outer (fading) angles. If you want a light bulb effect choose 30-60 for the bright angle, and anything larger than this for the fading angle. I choose 60 and 75.
To sort the color and intensity change brightness, this is the same with lights. Brightness is set up with standard RGB inputs, but the fourth is intensity. Lights have a default of 500, light_spots 200, which explains why they shunned due to dullness. Change this value to 400-600