I want to rotate Object around a Camera on mouse drag and also compatible with fingers on phone

Please check this

, I want to make this:

exactly as the first one..! I want to rotate Object around a Camera on mouse drag and also compatible with fingers on phone and also I want to limit the ZoomIn/Out..
I use this code below but the zoom has no limit and its not smooth.
Please help me..!
Thanks

Code (CSharp):

1. using System.Collections;
2. using System.Collections.Generic;
3. using UnityEngine;
4.  
5.  
6.  
7. public class MouseOrbit : MonoBehaviour {
8.     public Transform target;
9.     public float maxOffsetDistance = 2f;
10.     public float orbitSpeed = 15f;
11.     public float panSpeed = .5f;
12.     public float zoomSpeed = 3f;
13.     private Vector3 targetOffset = Vector3.zero;
14.     private Vector3 targetPosition;
15.    
16.  
17.  
18.     // Use this for initialization
19.     void Start() {
20.         if (target != null) transform.LookAt(target);
21.     }
22.  
23.  
24.  
25.     void Update() {
26.         targetPosition = target.position + targetOffset;
27.  
28.  
29.         if (target != null) {
30.             targetPosition = target.position + targetOffset;
31.  
32.             // Left Mouse to Orbit
33.             if (Input.GetMouseButton(0)) {
34.                 transform.RotateAround(targetPosition, Vector3.up, Input.GetAxis("Mouse X") * orbitSpeed);
35.                 float pitchAngle = Vector3.Angle(Vector3.up, transform.forward);
36.                 float pitchDelta = -Input.GetAxis("Mouse Y") * orbitSpeed;
37.                 float newAngle = Mathf.Clamp(pitchAngle + pitchDelta, 0f, 180f);
38.                 pitchDelta = newAngle - pitchAngle;
39.                 transform.RotateAround(targetPosition, transform.right, pitchDelta);
40.             }
41.             // Right Mouse To Pan
42.             if (Input.GetMouseButton(1)) {
43.                 Vector3 offset = transform.right * -Input.GetAxis("Mouse X") * panSpeed + transform.up * -Input.GetAxis("Mouse Y") * panSpeed;
44.                 Vector3 newTargetOffset = Vector3.ClampMagnitude(targetOffset + offset, maxOffsetDistance);
45.                 transform.position += newTargetOffset - targetOffset;
46.                 targetOffset = newTargetOffset;
47.             }
48.  
49.  
50.             // Scroll to Zoom
51.             transform.position += transform.forward * Input.GetAxis("Mouse ScrollWheel") * zoomSpeed;
52.  
53.         }
54.     }
55. }// CLASS ```