In order to be able to log in using Fido keys,, you will need to sign in to the your Okta account,, then from your user account dropdown select "Settings";
A new web page will now open titled "Account", in the section "Security Methods" you will be shown a list of currently available authentication methods, select the option "Security Key or Biometric Authenticator" click on the "Set up" button;

After verifying your identity, a window such as the following will be shown;

Click on "Set up", and in the popup window that opens select the option "Save another way";

Insert you Fido key into an available USB port, then select the option "use a phone tablet or security key";

When asked to sign in with your passkey select "Security key";l

At this point you will be asked to provide the PIN code that protects your Fido2 key;

Enter the PIN code for your key then click
, and you will be asked to touch the button on your key;

Provided you press the button on the Fido2 key in the allowed time, the passkey details will be stored on your Fido2 key.