This is another example of a resource post using the media block. With PDF files the Media block provides a preview of the PDF as well as a download button. Be sure to set up the Featured Image for the post so it shows up properly. You do have to upload this image manually. This is one disadvantage of this new approach. The old method used the PDF preview that WordPress automatically generated. But there were cases where the automatically generated preview would have errors. So this gives you more control over the images that show up as a preview in listings and search results.