How to put assests into an array

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

public class GameHandlerMapGeneration : MonoBehaviour
{
GameObject SpawnPointObj;

GameObject[] Obstacles;

public void Start()
{
    SpawnPointObj = GameObject.FindGameObjectsWithTag("SpawnPoint");
    
    
    
    
    foreach(GameObject SpawnPoint in SpawnPointObj)
    {
        print(SpawnPoint.transform.position);
        int index = Random.Range(0, Obstacles.Length);
        GameObject ObjBeingSpawned = Obstacles[index];

    }

you see that game object array thing that is called Obstacles. I need that array to contain all the obstacles in my game (i have many objects like landmines speedbumps etc) but i have only 2 obstacles that are generateable. They are in the assets thing. They are in a folder called Obstacles. These obstacles are just groups of single objects. Like i have my first obstacle called 5 cones (its just 5 traffic cones) and 10 cones (its the same thing but more). i want these obstacles in the array but how???

Declare Obstacles as public or [SerializeField]

You can then add the assets in the inspector. There is a small lock icon at the top right of your objects inspector that you can click and then you can select multiple assets in a row and drag them over instead of one by one.