How do I add a light?

To add a light, go to 2D mode. 

Tap the pencil in the top right corner.

Notice the different objects you can add by drawing different shapes. 

The light happens to be a V shape.  

If you don't want to draw it, tap the symbol and a light will appear on your set.

When you're done adding objects to your set, select 'Done' in the top right corner. 

If you prefer a lantern, instead of a spotlight, tap the spotlight in either mode and select 'Edit'.  Then you can change it and adjust the intensity and color.