How to spawn multiple prefabs at different spawn rates

I consider myself to be pretty beginner level when it comes to Unity and programing in C#. In the project I'm working on my goal for t$$anonymous$$s script is to have it be able to spawn different type of enemies at different times for each spawn point. Basically to create a single script for all spawn points instead of having to create a separate script for each enemy spawn point. T$$anonymous$$s is what I have so far.

 public class EnemyWaveSpawner : MonoBehaviour
 {
     public GameObject[] enemiesToSpawn;
 
     //public float spawnRate;
     //public float spawnStart;
     private float waitToSpawn;
     //public int[] waveStartNumber;
     private int currentWaveNumber;
     //private int waveCounter = 3;
     public WaveManager waves;
 
 
     // Start is called before the first frame update
     void Start()
     {
         waitToSpawn = 0f;
     }
 
     // Update is called once per frame
     void Update()
     {
         //SpawnManager();
         SpawnEnemy(waves.waveStartNumber[0], waves.enemySpawnNumber[0], waves.spawnRates[0]);
 
         currentWaveNumber = KaijuLevelManager.instance.waveNumber;
        
         waitToSpawn -= Time.deltaTime; 
         if (waitToSpawn <= 0)
         {
             waitToSpawn = 0;
         }
     }
 
     /*private void SpawnManager()
     {
         switch (waveCounter)
         {
             case 3:
                 SpawnEnemy(waves.waveStartNumber[0], waves.enemySpawnNumber[0], waves.spawnRates[0]);
                 break;
         }
     }*/
 
     private void SpawnEnemy(int waveStart, int t$$anonymous$$sSpawn, float spawnRate)
     {
         if (KaijuLevelManager.instance.enemiesActive && currentWaveNumber >= waveStart)
         {
             if (waitToSpawn <= 0)
             {
                 GameObject enemyClone = Instantiate(enemiesToSpawn[t$$anonymous$$sSpawn], transform.position, transform.rotation);
                 waitToSpawn = spawnRate;
             }
         }
     }
 }

T$$anonymous$$s script is still a work of progress. I figured out how to set it up so I can spawn different enemies of my choice and for each start at different waves. The problem I have is that I can't really figure out how to spawn them at different times. As you could probably tell in my script there's a single spawn timer counting down. I can already see how t$$anonymous$$s wont work for different spawn rates for each enemy. My first solution was to try put "waitToSpawn" local to the the function instead of the script like t$$anonymous$$s.

 private void SpawnEnemy(int waveStart, int t$$anonymous$$sSpawn, float spawnRate)
     {
         float t$$anonymous$$sWaitToSpawn = spawnRate;
         if (KaijuLevelManager.instance.enemiesActive && currentWaveNumber >= waveStart)
         {
             t$$anonymous$$sWaitToSpawn -= Time.deltaTime;
             if (t$$anonymous$$sWaitToSpawn <= 0)
             {
                 GameObject enemyClone = Instantiate(enemiesToSpawn[t$$anonymous$$sSpawn], transform.position, transform.rotation);
                 t$$anonymous$$sWaitToSpawn = spawnRate;
             }
         }
     }

The problem I run into when trying to do t$$anonymous$$s is that "t$$anonymous$$sWaitToSpawn" will not reset itself to equal "spawnRate". If I try to put "t$$anonymous$$sWaitToSpawn" at zero from the beginning then it'll continuously spawn the object non stop(it will eventually stop when the level manager stops its countdown and turn the bool, enemiesActive, false). At t$$anonymous$$s point I'm pretty much banging my head on the wall trying to figure t$$anonymous$$s out. Do you have any possible suggestions on how to precede forward?