Processes in Microsoft 365 for setting up Office apps, redeeming product keys, and activating licenses.
Jan,
Typically, activation is straightforward when you complete the install from your associated account.
Do you see any error messages that mention activation?
See https://support.microsoft.com/en-us/office/activate-office-5bd38f38-db92-448b-a982-ad170b1e187e.