A family of Microsoft spreadsheet software with tools for analyzing, charting, and communicating data.
Do you mean Microsoft 365, a subscription you pay monthly or yearly?
If so, as long as it is NOT Microsoft 365 Basic, you can install on as many devices as you want, as long as you don't sign in on more than 5 devices at the same time.
To install, Please go to https://account.microsoft.com/services
Sign in to the Microsoft account you used for the subscription.
You should then see your subscription listed. Find the option called "Install desktop versions of Microsoft 365 apps like Word, Excel and Powerpoint to your devices". It has a down arrow icon next to it.
Click on that. It should start downloading the installer file. Then you just need to run that installer file to install the apps.
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If it is a perpetual license, like a one-time purchase, called Office Home 2024 for example, you can only install on one device at a time.