Can't connect file blueprint to images - This page has no blueprint setup yet

I’ve seen some other posts about this (like this one), but for me this still doesn’t seem to work. If I’m honest, even after doing a couple of sites in Kirby 3, the whole files-system is completely abracadabra for me.

I have this blueprint in pages:

main_image:
    label: Main Image
    type: files
    multiple: false
    layout: cards
    empty: Select image
    template: image

And this is the blueprint in files (called image.yml):

fields:
    info:
        label: Title
        type: text
    copy:
        label: Credits
        type: text

But when clicking the image in panel I get:

This page has no blueprint setup yet

What can I do?

Without more context I assume this is supposed to be a files field, not a files section. The files field does not have a template option. You can assign a template for files that you upload via the field like this:

main_image:
    label: Main Image
    type: files
    multiple: false
    layout: cards
    empty: Select image
    uploads:
      template: image

Note that the template will not be assigned to already uploaded images.

Difference between files field and files section: