Can someone help me with my third person camera?

I want to create a good third person camera but i have some trouble: my camera can only follow my character and look at him, but cannot rotate around him.

here is my code:

 Vector3 offset = Vector3.zero;
 Vector3 velocity = Vector3.zero;

 public float distance = 10f;
 float currentDistance;
 float minDistance = 16f;
 float maxDistance = 20f;

 public float height = 8f;
 public float targetHeadHeight = 7f;

 float smooth = 0.3f;
 
 public Transform target; //for read target position

 void Awake(){
     offset = new Vector3 (target.position.x, (target.position.y + height), (target.position.z - distance));
     transform.position = offset;
 }

 void Update(){
     LookAtTarget ();
 }

 void LateUpdate(){
     UpdatePosition ();
 }

 void LookAtTarget(){
     Vector3 relativePos = target.position - transform.position;
     Vector3 y = new Vector3 (0, targetHeadHeight, 0);
     Quaternion newRotation = Quaternion.LookRotation (relativePos + y);
     transform.rotation = Quaternion.Slerp (transform.rotation, newRotation, 10f * Time.deltaTime);
 }
 

 void UpdatePosition(){
     currentDistance = Vector3.Distance (transform.position, target.position);

     if (currentDistance < minDistance) {
         currentDistance = minDistance;
     } else if (currentDistance > maxDistance) {
         currentDistance = maxDistance;
     }

     distance = currentDistance;

     offset = new Vector3 (target.position.x, (target.position.y + height), (target.position.z - distance));
     transform.position = Vector3.SmoothDamp (transform.position, offset, ref velocity , smooth);
 }