No, you don't. Logging in first or even having a Network User Id is not a requirement when you wish to add your computer to NoMachine Network. Adding a computer to Network is easy and can be done in the NoMachine Settings > Network > Machine > Connect.

Once the computer has been added to Network, it receives its Machine Id and Access Id. These details are then used by the person who wants to connect to that machine over the Network service. That user will use their Network User Id to login to Network and insert the Machine Id of the target computer to start the connection.