hello all, do we have any place to record "last login time" of user?

There is not such thing implemented in kratos. When dealing with such requirements you should think about what last login means: 1. Is it the time, when the user lets kratos verify its credentials during the real login? 2. Is it the time kratos issues a session? This happens not only when the verification from 1 is successful, but also when kratos renews the session. Session renewal can be triggered by different things. If only 1 is interesting for you, you can get the information by making use of a web hook, which would contact your specific end point to record that event. IMHO you should better think about something like, "when did the user use my system being authenticated".

Point #1, @User. Which web hook I can setup, @User?

the login after web hook. See also https://www.ory.sh/kratos/docs/next/reference/configuration