Like the thread title says, but you only have three days ... https://www.popsci.com/gear/lifetime-microsoft-office-sale/
It's a very good deal, especially for writers. You may (but probably won't) find a better price on Office Home and Student but, technically, H&S isn't supposed to be used for "commercial" purposes. Not that there's any likelihood that Microsoft is ever going to find out that you wrote your blockbuster great American (or English, or Chilean) novel using the H&S edition of Office, but if you can be both legal and thrifty, why not? That said, this is Office 2021, which has already been replaced by Office 2023. And it's a "perpetual" license, but "lifetime" does not include lifetime support. After October 13, 2026, there will be no more updates (including security updates). The software will continue to function, but those who often use Office to open files from external sources should be wary.
He who hesitates is lost. The sale is still on for the Mac version, but the Windows version is sold out. My computer runs Windows (of course).
The deals are back Softkey (which is a Microsoft "partner" of some sort) is offering the perpetual license versions of Office Pro 2019 and 2021 for Windows, and Office 2019 and 2021 with a Halloween discount. https://softkeyworld.com/product/microsoft-office-2021-professional-plus/?wpam_id=19 The site may pop up a window offering a 10% discount. I received an e-mail offering a 20% discount, using the discount code HALL20.