Here it is . . .
It cost me $1, as the background photo was a chargeable item (lots are free).
It’s not the same class as those from proper graphic artists, but it’s much better than the one I made with Amazon’s image creator, and seems great value for $1.
A good cover image is apparently very important – potential buyers are unlikely to assume you’ve taken care writing a great story if your front cover is horrible.
There are tutorials on the site, and on YouTube, so I’d recommend giving them a go.