SSH - what is the meaning of permission denied(publickey, password)?

The error message is typically displayed by the SSH client when you do not provide valid login credentials and the server refuses to grant you access.

After failing to authenticate successfully the ssh server responds with an error message that indicates what authentication methods it supports and is willing to accept (in order of preference). See: https://datatracker.ietf.org/doc/html/rfc4252#section-5.1

Those supported methods are the ones between the ( ) braces in the Permission denied (...) error.

Supported authentication methods are usually one or more of: GSSAPI-based authentication, host-based authentication, public key authentication, challenge-response authentication, and password authentication.