Rotate 3rd person Character according to mouse position

Hello , I am new in unity engine .. So, here is how the game should work: The character is running automatically in one direction, with an increasing speed over time , but he has to rotate and change his direction according to mouse position , but the camera following him should not rotate and continue following him in one direction.

What I did : I attached the camera to the character and then attached the following script to the character , but the camera rotates

 var camera = GameObject;
 var speed = 4.0;
 
 function Update () {
     // Generate a plane that intersects the transform's position with an upwards normal.
     var playerPlane = new Plane(Vector3.up, transform.position);
 
     // Generate a ray from the cursor position
     //var ray = Camera.main.ScreenPointToRay (Input.mousePosition);
     var ray = Camera.main.ScreenPointToRay (Input.mousePosition);
 
     // Determine the point where the cursor ray intersects the plane.
     // This will be the point that the object must look towards to be looking at the                 mouse.
     // Raycasting to a Plane object only gives us a distance, so we'll have to take the distance,
     //   then find the point along that ray that meets that distance.  This will be the point
     //   to look at.
 
     var hitdist = 0.0;
     // If the ray is parallel to the plane, Raycast will return false.
 
     if (playerPlane.Raycast (ray, hitdist)) {
         // Get the point along the ray that hits the calculated distance.
         var targetPoint = ray.GetPoint(hitdist);
 
         // Determine the target rotation.  This is the rotation if the transform looks at the target point.
 
         var targetRotation = Quaternion.LookRotation(targetPoint - transform.position);
 
         // Smoothly rotate towards the target point.
 
         transform.rotation = Quaternion.Slerp(transform.rotation, targetRotation, speed * Time.deltaTime);
 
 
     }
 }

the character also has the following scripts attached:

• Third Peron Controller

• Third Person Camera

Thank you.