Featured image for news page

Hi,

I would like to add a “featured image” to the front page of my site, displayed the same way as other pages with a featured image (for example: https://insertdisktwo.com/items-for-sale/

Ideally this is achieved through CSS and linking to a picture from the media folder. Thank you, really love your work!

The page I need help with: [log in to see the link]