Slides

I am wanting to make a slide with different backgrounds or use my personal pictures.
Here is the problem I am having: create a new slide, select template either just title or title and body, pro plus media tab is selected and i click on "your media library" to select my picture, but it puts the picture in my cue list and not as a background for my slide. what am I doing wrong or is this the only way?
I am using the free version so I can make sure this program will do everything we need in a presentation program. We are a small church, so I must be sure this program is the rigth on before spending money for it.

Thank you for your time and help
Ron

forgot one step, after I select the template, I click on background, pro plus media tab is selected and i click on "your media library" to select my picture..................................

First draw a large (full slide) box and set the type to "Media", then select the image from your library. No need to use the "Template" feature.