Processes in Microsoft 365 for setting up Office apps, redeeming product keys, and activating licenses.
Your Microsoft account used for the subscription will serve as your product key because the subscription is already linked to it
To verify, log in to your Microsoft account here: https://account.microsoft.com/services
Can you see your subscription there? If yes, open any Office app and sign in using the same Microsoft account. This should activate Office
If not, to clarify, do you mean the license came pre-installed with your laptop when you bought it? Were you given a product key to redeem?