How do you spawn random objects outside of screen?

Hi there,
I am trying to use object pooling to move my objects from out of range (as the player moves away from them) to into range, I am using random.range and placing the object within a certain bounding box (within range). I was wondering if there was a way that I can have the objects randomly spawn outside of the screen (so the player doesn’t see the object spawn in) but still have them spawn inside my preset limit. Essentially have them spawn within one box but not within the other that is inside the first box (this one is the screen), sorry if this makes no sense, I am just getting back into coding and can’t figure this one out, any help would be awesome!!

ps. here is some code that might help

using System.Collections.Generic;
using UnityEngine;

public class AsteroidLeader : MonoBehaviour {

IEnumerator AsteroidDetection()
    {
        while (true)
        {
            foreach (GameObject gameobject in asteroids)
            {
                float distances = Vector3.Distance(gameobject.transform.position, player.position);
                if (distances > spawnSize)
                {
                    gameobject.SetActive(false);
                    gameobject.transform.position = new Vector3(Random.Range(playerX - spawnSize, playerX + spawnSize), Random.Range(playerY - spawnSize, playerY + spawnSize),0f);
                    gameobject.SetActive(true);
                }
                yield return new WaitForEndOfFrame();
            }
        }
    }
}

Cheers

Ok so I figured out my issue, all I did when finding the position to spawn at was get a random vector from the players position using Random.IinsideUnitCircle.normalized and then times that vector by whatever range i wanted the asteroid to spawn between so Random.insideUnitCircle.normalized * Random.Range(35f, 60f)