Microsoft Office installation onto MacBook Pro

I am answering your question EXACTLY as written:

You don't haver to have a Microsoft account to download.

But long before you can save any changes you make, YES you will need a Microsoft account.

The download is assured safe because the software you download is Signed with Microsoft's Developer Certificate and Notarized to indicate it has not been modified since those binaries were created. NO Bypass of any kind is needed, only your Admin password.

Giving Microsft your payment method is safe as long as you are practicing due diligence and assure yourself you have made an excypted connection with Microsoft servers, not to Joesgarageshop.microsoft.com

If you don't feel safe downloading Microsoft 365 directly from Microsoft, you can download it from the Mac App Store. As Grant Bennet-Alder has stated, though, you'll need to create a Microsoft account and submit payment for the subscription service before you'll be able to use them.

If you're just looking for apps to open Word, Excel, and PowerPoint files, though...don't forget you have Pages, Numbers and Keynote available to you. (They're most likely preinstalled on your Mac, but if they aren't there, you can download free from the Mac App Store). These apps can read and write MS Office files with a decent amount of accurancy, and are, as I mentioned, free. And there's LibreOffice, another free alternative to MS Office.