This could be your posting page, or we can make it a static page as discussed on the current background page. There is no reason to have a posting/blog/sharing page unless you want. It is a lot of work to write something profound every week, which is typical when you have a blog.
My recommendation, start out with static pages and move towards a weekly blog/posting/sharing type of page in the future.
To add media, like a photo, above the tool bar above, there is an “add media button”. Click where you want the media inserted, such as a photo on the left or right of paragraph, click in front of the paragraph and then click on “add media” and chose. Then click on the photo and chose alignment in the first line of the tool bar. Left, center or right.