I see nothing unexpected in the file. When I select a whole paragraph, and then copy and paste it, I would expect the insertion point to end up in the following paragraph; this is because each paragraph in Word is terminated by a paragraph mark (¶) and because Word, by default, includes the paragraph mark when you select a paragraph.

To change the behavior, clear the "Use smart paragraph selection" option at File tab | Options | Advanced.

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Stefan Blom
Microsoft Word MVP

Microsoft 365 apps for business
Windows 11 Professional