Drop schadow

As Kevin has said, the fruit bowl layer appears to completely fill the document so a Layer Style > Drop Shadow would be applied outside the canvas, which is a nonsense,  The bowl's background needs to be transparent.  That way the drop shadow will be applied directly to the outside of the bowl.

This sort of object can present a problem with drop shadows as they can appear around the top of the object where there shouldn't be a shadow.  I have turned the shadow's oppacity way up to demonstrate this.

We can overcome this by right clicking with the cursor above the effect, and choosing Create Layer

This separates the layer styles onto seperate layers that we can mask to show just the area that should show.