This is an area which seems to trap unsuspecting first time users. Type /g to get the wizard up and read carefully. No need to add images twice, they can be used and reused again and again. Make sure you render the images at Large or Full size to avoid pixel scarcity. Add or remove pictures later. Alter key settings like aspect ratio, size, gutter size, screen width, margin, borders, animation etc.
But there’s nothing to stop you adding further content below or above for context and elaboration …