You do not need to enter the product key into the apps themselves. Activation happens via your login. Open any Office app (like Word or Excel).
: Open the downloaded .exe file. Select Yes when the User Account Control prompt appears. The installer will run in the background; stay online until it finishes. Microsoft Office 365 Install With Product Key
Once validated, your subscription is officially active and tied to your account. 2. Download the Installer You do not need to enter the product