I need help with spawning a singular object

I want to spawn an item ONCE within 10 different empty game objects with different positions at the start of the game ie spawning one singular item at ONE of the points/game objects. I have not found anything online or even on here about spawning a singular item within different set positions. i would like some help and i have less than three weeks to finish my project.

Not sure if I fully understand your question, but you want to spawn one object at some position randomly selected by positions you have defined via gameobjects. You want to be sure that your spawner only ever creates one object. I’m not sure when you want this object spawned, or if you want attempts to spawn a new one to destroy the old one or just not do anything. I’ll make it so any of these is possible.

The problem is fairly simple, you need to store the transforms of these position marker gameobjects in an array somewhere, store a reference to the prefab for the item, and eventually store a reference to the item itself. Then, when spawning, check if the item already exists. If so, return or destroy it. Otherwise, pick a random location from your array of transforms and spawn it there, assigning the item reference to the newly created item. The (untested) code looks something like this:

public Transform[] positions;
public GameObject itemPrefab;
public bool replace = false;
private GameObject itemInstance;

public void SpawnItem(){
     if(itemInstance != null){

     Transform placement = transform;
     if(positions.length > 0){
          placement = positions(Random.Range(0,positions.length));
     itemInstance = Instantiate(itemPrefab,placement.position,placement.rotation);

Then you can call SpawnItem() whenever you want to spawn the item. If you want the old item replaced with a new one, set replace to true, otherwise leave it false to just ignore any calls to spawn the item if it already exists (You would need to destroy it to spawn another one). Be sure to drag your position marking gameobjects into the positions array, and your prefab of the item into the itemPrefab reference. You can use it like this:

//Spawn an item when the game starts
void Start(){

//Spawn a new item if the old one is destroyed (set replace to false for this)
void Update(){

//Spawn an item when a trigger is entered
void OnTriggerEnter(){

//Etc. Spawn it however you want.