File is missing – Page Links To

Hi
Saw this plugin and this is something I really need but can not get it to work.
Permalink: https://orestone.net/about-us/ ?Edit
Links to: https://183.88.212.214/orestone/links/about-us Edit — this is a page file
According to instructions that is all I have to do, right?
There is no “about-us”-file in the link folder. Should there not be one?
Am I supposed to add the old file there? If so, I do not know how to do.
Thanks

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