Office Home & Student 2019 for Windows Product Key Only $9.9,
https://www.gamedealing.com/top-selling-games-microsoft-office-home-student-2019-for-windows-product-key-p-2631
It works on PC for 1user ONLY, binding with own account after activation.
Product minimum requirements system: 32/64 bit Windows 10
Check system key as below,
Windows 10 home oem $10.99 (not cheap msdn key. lifetime use.),
https://www.gamedealing.com/other-games-microsoft-windows-10-home-oem-key-p-2596
Windows 10 pro oem $11.99 (not cheap msdn key. lifetime use.),
https://www.gamedealing.com/other-games-microsoft-windows-10-professional-oem-key-p-2621
Reviews:
https://www.ozbargain.com.au/node/599118