Enable and disable options

Hi, I am making a scene with a first-person controller (moving a camera by using WSAD keys and rotating the camera by moving the mouse), Cube and UI Panel. My goal is the following: 1) Activate an UI Panel when I click on the Cube; 2) When the UI Panel appears, the first-person controller should be inactive so I can interact with the elements in the UI Panel; 3) Hide the UI Panel by clicking on a certain button in it (example the “X” button) and be able to walk and turn the camera in my scene again. I have already made the scripts of the ‘First-person controller’ and to ‘Cast a ray’ and ‘Detect’ an object. What I need is help for Enabling/Disabling the UI Panel. Then, when the UI Panel is shown on the screen, the first-person controller should be paused and again activated when the UI Panel is closed.

The code for detecting an object:

 using System.Collections;
 using UnityEngine;
 
 public class CLickAction : MonoBehaviour
 {
   
     void Update()
     {
         if (Input.GetMouseButtonDown(0))
         {
             Ray toMouse = Camera.main.ScreenPointToRay(Input.mousePosition);
             RaycastHit rhInfo;
             bool didHit = Physics.Raycast(toMouse, out rhInfo, 500.0f);
             if (didHit)
             {
                 //Call a funcion which will show the Panel
                 //Desable a function that moves camera by mouse movement. 
             }
             else
             {
                                 
             }
         }
     }
 }