Why can't I enter Outline View like the help says?

The LibreOffice 7.1 help says that we can access an Outline View:

Switches to outline view, where you can add, edit and reorganize slide titles and headings.

To access this command…

Choose View - Outline

But there is no “View - Outline” on my menus. Why isn’t it there? Do I need to enable it somehow?

This applies to Impress, you seem to look for it in Writer (keyword of your question).

In Writer, the “outline view” is offered in the Navigator. The Navigator is in the right side pane by clicking on the compass icon. F5 if not already present.

The outline of your document is shown in the Headings section.

Notice it works only if you use the Heading n family to mark up your headings (chapter, sub-chapter, …). In advanced use, other paragraphs may also be shown in the outline, but practice first with the Heading n style family.

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