I have been requested to buil an application with AR, and targeting VIVE™ PRO Headset, I don't have the physical headset. in android we used to use Virtual machine, Is there similar thing in VIVE™ ? I work with unity
You need a simulator to develop for HTC VIVE Pro without the device itself. To enable it, go to Edit ---> Preferences ---> VIU Settings and check the Simulator check-box. You can read more about this here.