Hi, Larry. Thank you for coming to the forum. My name is Femi. It is worth noting that this is a user community, and we are all users here, much like yourself. While we strive to assist and share insights, we are not Microsoft directly.
According to the article in https://support.microsoft.com/office/6d942360-b5ca-445f-a84d-6e8c66fc40d2 Microsoft has a plagiarism checker known as Similarity check;
"Similarity checker helps you create original work and cite the work of others in your Word documents. The similarity checker shows you how much content in your document is original, and it makes it easy to insert citations when necessary. With the mechanics of citations taken care of, you are freed up to focus on your writing. Your reader can tell what material originates with you, and the people you cite get credit where it's due.
Note: Similarity checker was announced in March, 2020 and continues to be released across Microsoft 365 subscriptions. It may take several weeks to reach your account. This feature is available only for English language text.
On the Home tab, choose Editor.
In the Editor pane, find Similarity, and click or tap Check for similarity to online sources.
When the check is complete, Editor shows you how much of your content matches text that it found online (indicated as a percent), and the number of distinct passages in the document for you to review.
To review the passages, click or tap Similarities reviewed. Editor takes you to the first passage, where you can choose whether or not to insert a citation. A link to the online content lets you judge for yourself whether attribution is warranted. If you decide not to add a citation, choose Ignore."
I hope this helps, let me know if this contradicts what you need. I remain helpful in answering any more of your questions.
Best Regards,
Femi.