The link you provided is the link to the confluence server documentation.
In the cloud, the name isn't "section", but "layouts". And the documentation for that is here: https://confluence.atlassian.com/confcloud/add-formatting-to-your-page-724764836.html#Addformattingtoyourpage-layouts
Hey Community 👋, Following the recent release of the new editor, we will be releasing the ability for users to convert existing pages from the legacy editor to the new editor. We’ve been resp...
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