Add perlin noise to blocky terrain

So im making a Terrain made out of blocks and I want to offset the blocks on the y-axis using perlin-noise but everyt$$anonymous$$ng I tried didnt work. So far all t$$anonymous$$s code does is create a flat plane made of blocks.

Also, please don't link to someone elses code, I want to do as much of t$$anonymous$$s on my own as possible for practice, thanks!

using System.Collections; using System.Collections.Generic; using UnityEngine;

 public class terrain : MonoBehaviour
 {
     public GameObject Grass;
     private GameObject copy;
     public int Width;
     public int Length;
     private Vector3 trans;
 
     // Start is called before the first frame update
     void Start()
     {

         trans = transform.position;
         
         for (int width = 0; width < Width; width++)
         {
             
             trans.x += 1;
             trans.z = 0;
             
             Quaternion rotation = Quaternion.Euler(0, 0, 0);
             
             copy = Instantiate(Grass, trans, rotation);
             copy.SetActive(true);           
 
             for (int length = 0; length < Length; length++)
             {
                 
                 trans.z += 1;
                 
                 copy = Instantiate(Grass, trans, rotation);
                 copy.SetActive(true);    
             }                   
         }
 
     }