The left sidebar is not something you build by hand. It comes straight from how your docs are related. Two things shape it: the parent of each doc, and its sidebar section.
Parents build the tree
When you open any doc, the sidebar shows that doc’s whole family: its top-level parent and every doc nested under it. So a doc with no children and no parent shows an empty sidebar, while a doc that is part of a family shows the full set.
To nest a doc, set its Parent in the editor. Most docs sites use one top-level doc per product, with everything else nested under it.
Sections group the list
Within a family, the Sidebar Section field adds grouping headings. Give several docs the same section text, like “Getting Started”, and they appear together under that heading. Leave it blank and the doc sits at the top, above the sections.
A simple structure that works
- Create one top-level doc for the product, with no parent.
- Create the rest with that doc as their Parent.
- Give each one a Sidebar Section to group it.
This is exactly how the docs you are reading are built: one “Divi Docs Maker” parent, with every page nested under it and grouped into sections.