PublicPress Plugin does not show image

I have a website with a static page as the homepage for my blog. And I am struggling to get it to do what I want it to do. I must be missing something obvious, any help will be much appreciated.

I have placed a PublicPress co-block on the home page to show my blog posts. Although this co-block shows clearly that there can be images, it does not show anything. On the post itself, the image is there.

What I want:
To show the latest post in full on the static post home page with a ‘previous’ and ‘next’ button
To show an index, with small versions of the image in the post, of other posts
To show the archive so that users can go there for a list of older posts

Am I using the wrong block? It seems like such a basic functionality, why does it not work?

Looking forward to you tips and tricks!
Nicky