SEO for internal pages

In Thomas’s recent author website review, he talked about the importance of a website’s internal pages being indexed in the search results, nested under the homepage, like this example from Misty M. Beller’s site:

Can anyone direct me to a good guide for optimizing my SEO for this? I’m using Yoast SEO and have the XML sitemap enabled, but I’m not always familiar enough with SEO terminology to know what I should research.