To add an image background
Open the page.
Drag a Section onto the page (One Column, two etc..).
Click on the section to select it.
On the right sidebar, select Background.
Click in the arrow to open the background editing options.
Click on the drop down arrow of Background and select Images.
Click on Insert new image to open My files.
Select the image.
Add the image. You can also edit the scroll effect
Preview using the Preview button on the top toolbar.
Save from the top toolbar.
Tip: As well as different page areas, you can add an image background to text boxes too.