Lead Developer
Sure, you can just add the image to the content using some HTML:
<img src="URL TO THE IMAGE" alt="" />
Add that into the content box where you want the image to show up and you should be good to go 🙂
Documentation: http://docs.generatepress.com/
Adding CSS: http://docs.generatepress.com/article/adding-css/
Ongoing Development: https://generatepress.com/ongoing-development