Hi,
do you mean after you have inserted your credentials into the NoMachine login window. Do you want to see the desktop and not have to login again? If so, on a Linux NoMachine server you can configure this directly on your system by setting autologin. Please check your system’s configuration manual to know exactly what to set but an article to start with is this:
‘https://vitux.com/how-to-enable-disable-automatic-login-in-ubuntu/’
Or do you mean that you want to start your connection automatically? If so, see this article
How to start the session by passing options to the client from command line
https://knowledgebase.nomachine.com/AR02P00963