Processes in Microsoft 365 for setting up Office apps, redeeming product keys, and activating licenses.
Sounds like you have Office 365 Education. That does have the 5 install count (installing at home is fine), but it is for your own use, that is why it only supports 1 email account It is not intended to be shared with other people. 365 Education is based on 365 Business.
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You can tell exactly which license. In any Office application, go to File menu > Account command. Look under the Office logo. A couple of lines down it will show the exact office bundle name.
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