Here you will find information about using this WIKI:

• DokuWiki - the engine of this wiki
• Formatting Syntax

To automatically add a summary on a page containing sub-pages, you can use “simplenavi” as follows:

{{Simplenavi>MY_FOLDER}}

(Of course, replace “MY_FOLDER” with the folder whose summary you want to display.)

More info on simplenavi here: https://www.dokuwiki.org/plugin:simplenavi