Assets-Images Not included in Gallery

Hi, I have completely set up the Bakery Pro theme an am in the process of customizing it. I have installed the demo content and it is displaying correctly.
Since I am using this theme for an Arts and Crafts website, I need to create and upload my own images and icons in place of the little pink and/or white images that show bakery products.
I see, however, that while the gallery shows many images, it is not complete and I am unable to change them.
The gallery does not show any of the images that are in these folders which are found under “Assets”
Partners
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Please explain to me how to access these images so I can replace them with my own.
Thank you.