To quickly add an image gallery, go to Edit Pages > Add Page > Gallery. Use the default page name "Gallery" or use your own. Click Done. Your new gallery page will include an Image Grid block and a 2 Column Video block to get you started. You can continue adding or deleting blocks as you customize your page.
Additional image blocks are found by going to Add Content > Photos & Videos.
The Image Grid includes 8 image thumbnails by default.
Add thumbnails by hovering on the block and clicking the green + sign.
Remove a thumbnail by hovering on it and clicking the red X.
The Image Grid block uses the "lightbox" feature. When visitors click a thumbnail, it will launch a full version of the image.