Use the File menu's Save As Package command to open the Package Document dialog.
The dialog's Summary section reports the numbers of fonts and images used in your document and alerts you to potential problems.
The total number of images may be larger than the sum of linked, missing and modified images because it also includes any that are embedded within the document.
You can choose to exclude all fonts and/or all images when creating a package.
To exclude individual items, delete them from the destination folder after the package has been created.
The dialog provides separate counts of items that are missing, modified or restricted. Investigate these before you proceed with packaging.
Affinity Publisher may inform you that it has failed to save the package, and that the package may be incomplete. One reason for this message is to remind you that some fonts or images are missing.
If you did not expect any fonts or images to be missing, try packaging the document again.
Always check that a package contains everything that is expected.