open camera on android with orientation?

Hi... I used this script to open device camera :

 public int selectedCam = 0;
     private WebCamTexture webCamTexture;
     public static double[] transMat = new double[16];
     
     void Start()
     {
         // Initialize the webCamTexture and apply the webcam stream on the object
         webCamTexture = new WebCamTexture();
         GetComponent<Renderer>().material.mainTexture = webCamTexture;
         webCamTexture.deviceName = WebCamTexture.devices[selectedCam].name;
         
         // Start streaming the images captured by the webcam into the texture
         webCamTexture.Play();
     }

• this script attached to a panel and the main camera looking at it .

My questions:

1 - how can I let the panel size as the screen size (fullscreen) ?

2- camera (panel) rotate with the device (orientation)

3- the objects in the opening camera are scaled . ( I mean the size of objects not correct ) , how can I fix that ?

thank you so much .....