Bitwarden Authenticator is a standalone app that is available for everyone, even non-Bitwarden customers.
In its current release, Bitwarden Authenticator generates time-based one-time passwords (TOTP) for users who want to add an extra layer of 2FA security to their logins.
There is a comprehensive roadmap planned with additional functionality.
Available for iOS and Android
Yes but you would still have 2FA.
You would still be using 2fa to access your vault. So in effect anything in that vault has more then 2 factors of authentication as it requires MFA just to get to the password.