How would I enable a camera when a button is pressed

Unity Engine
1

Hi guys, I need to write some code to enable a camera to focus on an object ( as well as disable other cameras in the level )

I already have the click this item to do this code done

I just need to know how to do this. I have 4 cameras in total , so the game flow is like this

arrow to move to camera 4 ------ GAME FOCUS 1 ----- Arrow to move to camera 2
(AT camera 1)

arrow to move to camera 1 ------ GAME FOCUS 2 ----- Arrow to move to camera 3

(AT camera 2)

2

The arrows are buttons FYI

3 
var lookatme : GameObject;
var padlight : GameObject;
var thatwasclicked : GameObject;
function Update () 

{

 if (Input.GetMouseButtonDown(0))
 {
        print("turn the cam please  .");
          var hit : RaycastHit;
        var ray : Ray = Camera.main.ScreenPointToRay(Input.mousePosition);
        if (Physics.Raycast(ray,hit,100.0))
       
        	 {
        	if(hit.transform.transform.gameObject == thatwasclicked )
        	
        	
        	
        	{
        var myCam : Camera = gameObject.find ("My Camera").GetComponent( SmoothLookAt);
			myCam.enabled = true ;
		var myCam.Target = gameObject = lookatme ;
			
        	}       	
        
			
        }
        }
        }

this is the code I have so far ?

Any suggestions