I am trying to understand the authentication flow of ssh, handshaking of client and remote server. I want to allow only specific ssh clients to ssh into the remote ssh server. To do this, I need to create a host key on the server as I know.
I used this command:

I have to VMs.

I am trying to launch a GUI based application on a target machine running linux (I am not trying to view or use the application through ssh, I just want it running in the background on the target machine).

Using GCP VM Instance, I’m connected via ssh, not serial port. When I type w or who or finger I get the following output: