Help with disabling camera movement and showing cursor on pause menu

Hi all,

Preface: I have zero scripting/coding experience.

I'm an M.Des art school student trying to make a (first person) virtual art installation for my masters research project given in-person installations are a no-go currently. I've managed to build most of the game using tutorials and copy-pasting scripts from the internet, but I've come up against something that I think requires some specific scripting, which I'm unable to do.

Basically, I've created a pause menu (using Brackeys' pause menu tutorial) however the camera continues to move even while in the menu. I've found multiple threads and questions covering this but they either assume some level of scripting knowledge or don't seem to apply to my camera movement script - I copy-pasted a "smooth mouse look" script as I wasn't a fan of the robotic camera movement of other scripts.

I'm also not sure how to unlock the cursor for the pause menu. Any help would be very much appreciated, but as I said, please know that my knowledge of scripting is essentially nothing! I would love to spend the time to learn, but time is something I don't have much of currently with the need to focus on creating the artistic content for the installation.

Here are the pause menu and camera movement scripts:

Pause menu:

 using System.Collections;
 using System.Collections.Generic;
 using UnityEngine;
 
 public class PauseMenu : MonoBehaviour
 {
     public static bool GameIsPaused = false;
     public GameObject pauseMenuUI;
 
     // Update is called once per frame
     void Update()
     {
 
         if (Input.GetKeyDown(KeyCode.Return))
         {
 
 
             if (GameIsPaused)
             {
                 Resume();
             }
             else
             {
                 Pause();
             }
         }
     }
 
     public void Resume()
     {
         pauseMenuUI.SetActive(false);
         Time.timeScale = 1f;
         GameIsPaused = false;
     }
     void Pause()
 
     {
         pauseMenuUI.SetActive(true);
         Time.timeScale = 0f;
         GameIsPaused = true;
     }
     public void LoadMenu()
     {
         Debug.Log("Loading Game...");
     }
     public void QuitGame()
     {
         Debug.Log("Quitting Game...");
     }
 }

Camera movement:

 using UnityEngine;
 
 [AddComponentMenu("Camera/Simple Smooth Mouse Look ")]
 public class SimpleSmoothMouseLook : MonoBehaviour
 {
     Vector2 _mouseAbsolute;
     Vector2 _smoothMouse;
 
     public Vector2 clampInDegrees = new Vector2(360, 180);
     public bool lockCursor;
     public Vector2 sensitivity = new Vector2(2, 2);
     public Vector2 smoothing = new Vector2(3, 3);
     public Vector2 targetDirection;
     public Vector2 targetCharacterDirection;
 
     // Assign this if there's a parent object controlling motion, such as a Character Controller.
     // Yaw rotation will affect this object instead of the camera if set.
     public GameObject characterBody;
 
     void Start()
     {
         // Set target direction to the camera's initial orientation.
         targetDirection = transform.localRotation.eulerAngles;
 
         // Set target direction for the character body to its inital state.
         if (characterBody)
             targetCharacterDirection = characterBody.transform.localRotation.eulerAngles;
     }
 
     void Update()
     {
         // Ensure the cursor is always locked when set
         if (lockCursor)
         {
             Cursor.lockState = CursorLockMode.Locked;
         }
 
         // Allow the script to clamp based on a desired target value.
         var targetOrientation = Quaternion.Euler(targetDirection);
         var targetCharacterOrientation = Quaternion.Euler(targetCharacterDirection);
 
         // Get raw mouse input for a cleaner reading on more sensitive mice.
         var mouseDelta = new Vector2(Input.GetAxisRaw("Mouse X"), Input.GetAxisRaw("Mouse Y"));
 
         // Scale input against the sensitivity setting and multiply that against the smoothing value.
         mouseDelta = Vector2.Scale(mouseDelta, new Vector2(sensitivity.x * smoothing.x, sensitivity.y * smoothing.y));
 
         // Interpolate mouse movement over time to apply smoothing delta.
         _smoothMouse.x = Mathf.Lerp(_smoothMouse.x, mouseDelta.x, 1f / smoothing.x);
         _smoothMouse.y = Mathf.Lerp(_smoothMouse.y, mouseDelta.y, 1f / smoothing.y);
 
         // Find the absolute mouse movement value from point zero.
         _mouseAbsolute += _smoothMouse;
 
         // Clamp and apply the local x value first, so as not to be affected by world transforms.
         if (clampInDegrees.x < 360)
             _mouseAbsolute.x = Mathf.Clamp(_mouseAbsolute.x, -clampInDegrees.x * 0.5f, clampInDegrees.x * 0.5f);
 
         // Then clamp and apply the global y value.
         if (clampInDegrees.y < 360)
             _mouseAbsolute.y = Mathf.Clamp(_mouseAbsolute.y, -clampInDegrees.y * 0.5f, clampInDegrees.y * 0.5f);
 
         transform.localRotation = Quaternion.AngleAxis(-_mouseAbsolute.y, targetOrientation * Vector3.right) * targetOrientation;
 
         // If there's a character body that acts as a parent to the camera
         if (characterBody)
         {
             var yRotation = Quaternion.AngleAxis(_mouseAbsolute.x, Vector3.up);
             characterBody.transform.localRotation = yRotation * targetCharacterOrientation;
         }
         else
         {
             var yRotation = Quaternion.AngleAxis(_mouseAbsolute.x, transform.InverseTransformDirection(Vector3.up));
             transform.localRotation *= yRotation;
         }
     }
 }
 

Thanks!