Donate button in Lite

Documentation for setting up a “donate button” is sadly lacking on the GP Lite site. The one article I found there says “The donation section can be easily customized within the WordPress customizer by navigating to Appearance > Customize within the WordPress admin. Link the “Donate” button to another page or your external donation service, such as PayPal.”

By trial and error I discovered I’d been mislead. The full path is Appearance > Customize > Theme options > HomePage options. However there is no indication of how to complete the process — just a bunch of fields I don’t know what to do with. It says nothing at all about how to make the button appear on the Donate page I already created.

Since this feature is so basic to a non-profit startup desperate to raise funds, does anyone have more complete help info on this.

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