It is generally not possible to launch an application, open a file, go to a url, etc., directly on the system under test (SUT) without going through the user interface on that system.
The VNC protocol allows you to send only mouse and keyboard events and to receive screen images. This limitation means that it’s just not possible to send a more complex instruction to the SUT because no standard VNC server would understand it. So in most cases, you need to script the same actions that a user would perform to complete a task. Note: The primary exception to this rule is that with most VNC servers, you can get and set values on the clipboard of the SUT using the RemoteClipboard() function.
One way to manage this is to script the actions necessary to launch the application, open the file, or navigate to the desired url on your SUT, and then create a handler using that code, that can be called whenever you need to execute that action. See the related FAQ How can I launch an application on the SUT? for more information on how to do this.
For information about scripting user actions, see Creating Tests with Eggplant Functional.