I want to make a Cube surface

Hello, I want to make a cube with different heightmaps on each Side. And thats what i got. Now i want to wrap this like a Cube, but i am not sure how to do this. If i Rotate it manully each face is much more aweay than before. If i ROtate it around a certain Point with script they are spreat all over the place.

 public class Landscape : MonoBehaviour {
     public int width = 128;
     public int depth = 128;
     public int heightScale = 20;
     public float detailScale = 25f; 
 
     public GameObject cube;
     public Transform landscapeMid;
     public Transform landscapeLeft;
     public Transform landscapeLeft2;
     public Transform landscapeRight;
     public Transform landscapeTop;
     public Transform landscapeBottom;
 
 
     void Start(){
         for (int z = 0; z < depth; z++) {
             for (int x = 0; x < width; x++) {
                 int y = 0;//(int) (Mathf.PerlinNoise(x/detailScale,z/detailScale)*heightScale);
                 Vector3 blockPos = new Vector3 (x, y, z);
                 Instantiate (cube, blockPos, Quaternion.identity, landscapeMid);
             }
         }
         for (int z = 0; z < depth; z++) {
             for (int x = -width; x < -1; x++) {
                 int y = 0;//(int) (Mathf.PerlinNoise(x/detailScale,z/detailScale)*heightScale);
                 Vector3 blockPos = new Vector3 (x, y, z);
                 Instantiate (cube, blockPos, Quaternion.identity, landscapeLeft);
             }
         }
         for (int z = 0; z < depth; z++) {
             for (int x = -(2*width); x < -width-1; x++) {
                 int y = 0;//(int) (Mathf.PerlinNoise(x/detailScale,z/detailScale)*heightScale);
                 Vector3 blockPos = new Vector3 (x, y, z);
                 Instantiate (cube, blockPos, Quaternion.identity, landscapeLeft2);
             }
         }
         for (int z = 0; z < depth; z++) {
             for (int x = width; x < (2*width)-1; x++) {
                 int y = 0;//(int) (Mathf.PerlinNoise(x/detailScale,z/detailScale)*heightScale);
                 Vector3 blockPos = new Vector3 (x, y, z);
                 Instantiate (cube, blockPos, Quaternion.identity, landscapeRight);
                 //landscapeRight.RotateAround (landscapeMid.transform.position, Vector3.forward, 90);
             }
         }
         for (int z = depth+1; z < (2*depth); z++) {
             for (int x = 0; x < width; x++) {
                 int y = 0;//(int) (Mathf.PerlinNoise(x/detailScale,z/detailScale)*heightScale);
                 Vector3 blockPos = new Vector3 (x, y, z);
                 Instantiate (cube, blockPos, Quaternion.identity, landscapeTop);
                 //landscapeTop.RotateAround (new Vector3(width / 2, 0, depth / 2),Vector3.forward,90);
             }
         }
         for (int z = -depth; z < -1; z++) {
             for (int x = 0; x < width; x++) {
                 int y = 0;//(int) (Mathf.PerlinNoise(x/detailScale,z/detailScale)*heightScale);
                 Vector3 blockPos = new Vector3 (x, y, z);
                 Instantiate (cube, blockPos, Quaternion.identity, landscapeBottom);
             }
         }
 
 
     }
 
 
 
 }

And this is my code. Iw ould be very Happy if someone could help me. Ps: Sry for my english.