Editing with Divi Visual Editor
The website uses something called Divi Visual Builder, which means you can edit the site in a visual way. Here is a video tutorial on getting started:
Here is a tutorial if you prefer something written: https://www.elegantthemes.com/documentation/divi/visual-builder/
Generally speaking, you can log in, go to the page you’re after, click ‘Enable Visual Builder’, click on the section you want to edit, make your changes, then click ‘Save’. I recommend having 2 tabs open – one on the edit screen and one on the regular page as it would be seen so you can refresh after each save and see the effect of your changes.
A quick look around
This video will give you an introduction to your new site, compared to the old.