Chances are it will simply require some stacking of masked layers with blending modes and a bunch of effects. Without seeing your footage or concept art nobody can advise specifically, though. Even if 3D lights are somehow invoilved/ could be used, there's a big likelihood that more work is needed, as flatly lit layers by themselves don't do that much.
If you want to use lights then the spotlight is the right choice. You can make the beam visible using Trapcode LUX, or you can fake it by using 3D solid blend modes and falloff. An even easier way to fake a light beam is to draw a feathered mask in the shape of the beam on a shape layer with a gradient and use a blend mode.
To give you the most efficient workflow we really need to see your composition with the modified properties of the layers revealed. There are just way too many possible workflows to go into all of them. Before LUX I used blend modes and masks a lot.
I took some sample Arri Alexa footage and added a shape layer with a feathered mask to create this new quick tip inspired by your question.