If you'd like the page where your podcasts are displayed to have a certain layout, that is determined by your theme. In Divi where you have the ability to create a "web page" with the page builder, it's harder to see what WordPress is doing for you in the background and this can be confusing. Let's first look at a few WordPress concepts along with how the Seriously Simple Podcasting plugin uses those features.
When you have the SSP plugin installed and setup, it creates two pages: one for the episode, a Podcast Post using the single.php template file, and one page for the list of podcasts, an Archive Page using the archive.php template file. Both of those template files are like a container, they have pre-constructed areas like the navigation and footer areas and then a blank section where SSP adds the player or a list of podcasts. These pages are created dynamically. Out of the box and depending on your link structure the SSP podcast archive page can be found at the URL yourdomain.com/podcast and the episode page will be yourdomain.com/podcast-title.
In Divi, where you can construct pages with the builder, if you want to make any changes to the pages created dynamically for you, there are specific instructions to follow from the theme creator. SSP creates a Custom Post Type and to work with the Divi builder on your Podcast Episode, you first need to enable that Post Type in Divi https://www.elegantthemes.com/blog/theme-releases/divi-custom-post-types.
For the archive page, you can use the standard page created from archive.php template or you can follow the theme developer's tutorials to use the Divi them builder to get a different look https://www.elegantthemes.com/documentation/divi/the-divi-theme-builder/.
For more detailed help, reach out to the Elegant Themes support team and let them know you are working with the Seriously Simple Podcasting plugin and they will be able to help you get the theme to work with your podcast content.