Welcome Bob Hardy,
A Windows Hello PIN is separate from your Microsoft account password. It is used to sign in to a particular Windows device, and the PIN is associated with that device.
To maintain or update your PIN in Windows 10, open Settings > Accounts > Sign-in options, select PIN (Windows Hello), and then select Change PIN. You will need to enter your existing PIN before creating a new one.
If you no longer remember the PIN, select I forgot my PIN and follow the prompts to verify your account and create a new PIN.
You can find Microsoft’s instructions here: https://support.microsoft.com/en-us/windows/security/change-or-reset-your-pin-in-windows
Looking forward to your update.