Hi GD_501 My Name is Jen A, Thank you for reaching out to us.
I am sorry for this inconvenience / Do not worry, I will help you sort this issue/Rest assured that I will do my best to assist you with this matter.
To add a security key as a sign in method for your Microsoft account: Go to the Microsoft account page and sign in as you normally would. Select Security > More security options. Select Add a new way to sign in or verify. Select Use a security key. Identify what type of key you have (USB or NFC) and select Next.
Sign in to your account with a security key https://support.microsoft.com/en-us/topic/sign-in-to-your-account-with-a-security-key-b23a2a45-6ab8-4c86-9f22-bcadf60235aa
Set up a security key as your verification method https://support.microsoft.com/en-us/account-billing/set-up-a-security-key-as-your-verification-method-2911cacd-efa5-4593-ae22-e09ae14c6698#:~:text=Go%20to%20the%20My%20Profile,USB%20device%20or%20NFC%20device.
Let us know how it goes, we're here to help you further if needed. Jen A.