Adding Focus and Bokeh
In the Camera Tab of the studio you find a Toggle Button to switch "Autofocus" on or off. Turning it off switches to Manual Focus.
When Autofocus is turned on the focus of the virtual camera will always be set on the last product selected in the scene. The focus will be on the surface of the product.
Once the manual focus is activated you can set a new focus point by right clicking on your target in the scene. The focus will be set on the first object intersecting with a virtual ray "shot" from the position of the right click.
Depth of Field
Changing the Depth of Field will change the strength of the blur of the parts of the photo that are out of focus. The further away an object is from the focus point the blurrier it will be.