o add or adjust titles and captions, open the Project Page via the Pages panel, and double-click the image thumbnail.
Titles and captions display below landscape images, and below or beside portrait images. Use the Show Project Captions to display or hide all image names and description text.
If you’ve selected Image Alignment: Center and checked Show Project Captions, you can further adjust where the captions display on the page with the Portrait and Square Caption Style and Landscape Caption Style tweaks.
For either tweak, choosing Standard displays the caption directly below the image, and Offset moves the caption further down, equally spaced from the next image.