Hello and welcome!
There are different versions of Microsoft's Office 365 for Mac.
Most require subscriptions; other is a one-time purchase,
and all of these require download (code) from MS Servers.
• Compare Microsoft 365 Plans for Mac (formerly Office 365) - Microsoft Store
https://www.microsoft.com/en-us/microsoft-365/buy/compare-microsoft-365-products-for-mac
And there also is the Student version, for verified students;
depending on location & status, this 'online version' is free.
• Student discount for Microsoft Office (Office in Education)
https://support.microsoft.com/en-us/topic/student-discount-for-microsoft-office-office-in-education-59d471cf-d851-a798-e9b6-68764754d496
"Student discount for Microsoft Office (Office in Education) If you're a student or teacher you
are eligible to get the online version of Microsoft Office for free, plus 1 TB of online storage."
[Good for the only the duration one is enrolled at eligible institution; online files may evaporate.]
Free Microsoft Office 365 for Schools & Students | Microsoft Education (ask about Mac/PC version)
https://www.microsoft.com/en-us/education/products/office
(This online ^ version likely requires an adequate internet connection to interface with MS server.)
• Microsoft Office Home and Student 2019 (1 Mac) - Apple $150 - [Limited time offer on this site]
https://www.apple.com/shop/product/HP7C2LL/A/microsoft-office-home-and-student-2019-1-mac
Another option would be download free-ware office suite "LibreOffice", it has good reputation.
• macOS | LibreOffice- Free Office Suite - Based on OpenOffice - Compatible with Microsoft
https://www.libreoffice.org/get-help/install-howto/macos/
Slightly older & newer download versions available from Download LibreOffice, download menu.
..This is worth an effort to try; and is an affordable first-choice to use & learn about..
While Microsoft® products have Sales & Support ~ on their own branded website.
Apple Support Communities is often unofficially staffed 'by volunteers' from all over!