The Knowledge In Focus web part is a pre-configured In Focus web part which is added by default on a number of Atlas page templates. On some page templates which include this web part it may be named "Latest Knowledge" showing the most recent Knowledge articles in the current area or "Related Knowledge" showing Knowledge articles with the same Knowledge Type tag as the current article.
Each tile shows the title, image and date for the article. Users can go to a specific article by clicking the title or image, and page through the available Knowledge using the arrows at the top right.
Add Knowledge pages
Knowledge pages are created via the Add It wizard. You can follow the steps to create them here: Adding Knowledge Pages
Edit or Delete existing Knowledge pages
To Edit or Delete Atlas content please check this article: Edit or Delete Atlas content
For Knowledge pages, because these are Pages you can also Edit them by navigating to the specific page and clicking Edit in the top right.
You can customise the layout and query of a Knowledge In Focus web part by editing the page, then editing the web part and modifying the configuration options. All the configuration options for In Focus web parts are described in the linked article: Configuration for In Focus web parts