public class CameraController : MonoBehaviour //The script should be on the camera or on the player if it is a sphere
{
Vector2 rotation = Vector2.zero;
public float speed = 3; //the sensibility
void Update ()
{
rotation.y += Input.GetAxis("Mouse X");
rotation.x += -Input.GetAxis("Mouse Y");
transform.eulerAngles = (Vector2)rotation * speed;
}
}