Hi, I'm Bernard. I'm happy to help!
Just to confirm, have you previously activated this Windows license on a different PC, or is this the first time you're trying to activate it after purchasing it?
A Windows license is a digital license that is linked to your Microsoft account. If you've purchased the license but haven't activated it yet, kindly follow the steps below:
Go to Settings > System > Activation
Then add your Microsoft Account.
For reference: https://support.microsoft.com/en-US/accounts-billing/manage/add-your-microsoft-account-to-your-digital-license
https://support.microsoft.com/en-US/Windows/activation/activate-windows