Random generation of random asteroids

Here's the code I've written to achieve this goal. I've been revising this post as I've added key elements. Namely, it now does assign random size, mass and force to the asteroids. The trick was apparently to make my instantiated prefabs also GameObjects and then to use arrays to modify components values of each clone.

The values chosen suit my project but you can change them for yours. If you see anything that could be improved, let me know.

 using System.Collections;
 using System.Collections.Generic;
 using UnityEngine;
 
 public class Asteroides : MonoBehaviour {
 
     // Instantiates prefabs in boxed terrain.
 
     public GameObject[] Asteroid;
     private int nombreDobjets;
     private int index;
     private Rigidbody[] rb;
     private ConstantForce[] cf;
 
     void Start()
     {
         nombreDobjets = Random.Range(888, 1234);
         Vector3 TailleTerrain = GameObject.Find("Terrain").GetComponent<Terrain>().terrainData.size;
         rb = new Rigidbody[nombreDobjets];
         cf = new ConstantForce[nombreDobjets];
 
         for (int i = 0; i < nombreDobjets; i++)
         {
             index = Random.Range(0, 6);
 
             Vector3 pos = new Vector3(Random.Range(0, TailleTerrain.x), Random.Range(0, TailleTerrain.y), Random.Range(0, TailleTerrain.z));
 
             GameObject go = Instantiate(Asteroid[index], pos, Quaternion.identity) as GameObject;
 
             go.AddComponent<Rigidbody>();
             go.AddComponent<CapsuleCollider>();
             go.AddComponent<ConstantForce>();
             go.transform.localScale += new Vector3(Random.Range(0, 2f), Random.Range(0, 2f), Random.Range(0, 2f));
 
             rb[i] = go.GetComponent<Rigidbody>();
             cf[i] = go.GetComponent<ConstantForce>();
             rb[i].mass = Random.Range(345, 1000);
             rb[i].AddForce(Random.Range(0, 23), Random.Range(0, 23), 0, ForceMode.Acceleration);
             rb[i].AddTorque(Random.Range(0, 23), Random.Range(0, 23), Random.Range(0, 23), ForceMode.Acceleration);
             cf[i].force = new Vector3(0,188,0);
         }
     }