How to stop movement script on void start and resume after.

Hello! I am having trouble getting this script to work.

What i want is: On Void Start (So the moment the scene starts) i want my movement to be disabled, then after a total of 12 seconds, i want my movement to be enabled again.

It's not that hard to do but i am still very new to coding and appriciate all help i can get! Thank you!

My script(c#):

 using System.Collections;
 using System.Collections.Generic;
 using UnityEngine;
 
 public class CharacterController : MonoBehaviour
 {
     private bool Movement;
 
     public float speed = 10.0F;
     // Use this for initialization
     void Start()
     {
         Cursor.lockState = CursorLockMode.Locked;
         StartCoroutine(ActivateMovement());
         Movement = false;
     }
 
     // Update is called once per frame
     void Update()
     {
         if (Movement = true)
         {
             float translation = Input.GetAxis("Vertical") * speed;
             float straffe = Input.GetAxis("Horizontal") * speed;
             translation *= Time.deltaTime;
             straffe *= Time.deltaTime;
             transform.Translate(straffe, 0, translation);
 
             if (Input.GetKeyDown("escape"))
             {
                 Cursor.lockState = CursorLockMode.None;
             }
         }
     }
 
     IEnumerator ActivateMovement()
     {
         yield return new WaitForSecondsRealtime(12);
         Movement = true;
     }
 }