If you bought a retail disc, the key is usually on a sticker inside the DVD case or on a separate card.
Check your email for a confirmation receipt from the Microsoft Store or the retailer where you bought it. activation key word 2016
How to find product key for Microsoft Office already installed If you bought a retail disc, the key
Using an invalid or pirated activation key can result in: If you bought a retail disc
That being said, here are some general facts about activation keys for Microsoft Office 2016: