A Microsoft file hosting and synchronization service.
Hello Cecelia Binford, Welcome to the Microsoft community. The product key is only used when the product is bound to an account, if you did not get a product key when you purchased Microsoft 365, then it means that the Microsoft 365 you purchased is directly bound to your Microsoft account.
Have you successfully shared your Microsoft 365 with others? You don't need to give the product key to the person you share it with, after you share your Microsoft 365 with other people, if other people's accounts also successfully get the Microsoft 365 you shared, they can use their accounts to log in to the Office programs and use them without having to activate the product with the key.SincerelyCarlos - MSFT | Microsoft Community Support Specialisto