You cannot force a remote connection to the physical display whilst the checkbox for “Require permission to let remote users connect” is checked in the Security settings of the server (the PC you want to connec to). Take a look at the tutorial I passed to you in your other topic, and you should also look at the Guide here: https://www.nomachine.com/DT10O00155#2.2. If that checkbox is ticked, it is assumed the owner is physically sitting in front of the computer (server) and can accept the incoming connection when prompted.
The first checkbox you see in the Security tab lets you decide whether the server can accept the incoming connection automatically or ask for the desktop owner’s authorization. Quoting the guide:
“Select Require permission to let remote users connect when the explicit approval of the desktop owner is necessary. This option applies only to connections to the physical desktop when the connecting user is not the desktop owner. If the incoming user is the desktop owner, he/she will always connect and no request for authorization is issued.”
The request for desktop owner’s authorization is enabled by default. If the owner of the desktop has left their desk, then you should ask them to configure NoMachine access accordingly in order to share their computer with you.