Slide toolbar format (no option for FILL)

Version 5.2.04. The option to fill the background for a slide is missing in the newest update.
I have an older version and have gone to your instructions page, but can not follow the instructions because there is no option under format to FILL the background of the slide.
I do see an icon that is fill on the toolbar but do know how to use it, tried several different methods.

Please help.