you can create the new page by writing the link to it and then editing the page.
For example this is a link to a page called "domoticz" https://openwrt.org/docs/guide-user/services/automation/domoticz
Which does not exist yet. Click on the pencil button on the right to edit/create it.
You can edit the link however you like and it will land in the same "there is no page yet" page and you will be able to create a page there. https://openwrt.org/docs/guide-user/services/automation/domoticz_another_page
The page made with that link will then appear automatically in the "automation" category in other pages that show it, like here https://openwrt.org/docs/guide-user/services/automation/start
@tmomas is there a better way to create a new page in a specific place? Do we have something like "create a new page" page/template/thing that is a bit more intuitive and user-friendly than manually editing the URL in the browser?