Mouse on target

I want to make a game with boat and when you are close to the target(boat),
and you point the mouse on it, it will turn like mouse for get in, and when you click you are in the boat.
I believe in you guys. I always will.
Hope is my everything

you can add your raycast function a if checking by object name. if hits of an target name than add another functions for clicking and boat.

for example
var hit : RaycastHit;

 if (Physics.Raycast(transform.position, transform.TransformDirection(Vector3(0,0,1)), hit, 5))
     	if( == "Boat"){
              //give an info with gui text in here
     		if((Input.GetMouseButtonUp (0)))
                   //Get on the boat function

You may need to deal with raycasting in some code so here is a reference

Click this