Add an authenticator app or a passkey. Both work alongside your password, and with Sign in with Google.
Two-factor authentication
Turn it on from your account settings and scan the code with any authenticator app. From then on, signing in asks for a six-digit code after your password.
It applies however you sign in — including with Google.
Passkeys
A passkey signs you in with your device's own fingerprint, face or screen lock. No password to remember and nothing to type. Add one from your account settings; you can have several, one per device.
Sign in with Google
If you signed up with Google you have no password by default. You can set one at any time through "forgot password", which also gives you a second way in if you ever lose access to the Google account.
If you lose your authenticator
Contact support. You will be asked to confirm your identity before it is reset — that is the point of it, and there is no self-service route around it.