The login screen will show the last used method on the next login.
If you login once with the password, then in the next login it will show the password box.
If you swipe your finger on login, the next time it will show the biometric login icon.
I'm not sure if there is a way to show the password box all the time, other than disabling the fingerprint reader (which would defeat the purpose
Will check if it is possible and get back