To span your photos across two pages, follow the step-by-step below:
Place or position it so it cross the middle of the two pages
Turn the "Span" feature on (sometimes it is automatically on)
And you are done! Please check the screenshot below for a visual representation:

📝 Note: The 'Span' feature is also applicable to stickers. However, for text, span feature is not available. We recommend using 2 separate text boxes to span the text across the spread.