How to insert a gallery

Hello, I’ve been trying to insert a gallery in my page but can’t figure out how. I’ve already made a page named “Gallery” that has the gallery I want to use. In Customize > Frontpage Sections > Gallery I’ve chosen “Page” from the dropdown menu of Select Gallery Source and “Gallery” from Select Gallery Page. Nothing shows. Can’t figure out what the “Select a page which have content contain [gallery] shortcode.” message means. Please do not direct me here https://codex.www.ads-software.com/The_WordPress_Gallery that redirects here https://www.ads-software.com/support/article/inserting-images-into-posts-and-pages/ Can’t find anything that can solve my issue there.
Thank you

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