To start working with banners, you should go to admin panel and open Themes section, choose your current theme and click ‘Customize theme’button to open it.
Now scroll down and search for Custom blocks section which contains banner settings. Click Choose file button under Showcase position, search for your custom image on your computer and upload it replacing the default one.
Replace images for other banners in the same way.
After you’re done – click Publish changes button for the changes to take place and open the Home page, you will see custom images instead of the default ones.
Banner text and links can be managed in the same way: paste your text in Text filed and links – in Link field and publish the changes to save them.