Laser bolt stream is not what I want to happen.

Questions & Answers
1

In my game, the enemies don’t shoot one laser at a time, they shoot a stream of lasers. Help?
using UnityEngine;
using System.Collections;

public class EnemyMove : MonoBehaviour 
{
	public float timeBetweenAttacks;
	public GameObject shot;
	public Transform shotSpawn;
	public Transform shotSpawn1;
	public AudioClip laser;
   	
	Transform player;
	//PlayerHealth playerHealth;      
    	//EnemyHealth EnemyHealth;        
    	NavMeshAgent nav;                

    	void Awake ()
	{
		
		player = GameObject.FindGameObjectWithTag ("Player").transform;
          	//playerHealth = player.GetComponent <PlayerHealth> ();
        	//EnemyHealth = GetComponent <EnemyHealth> ();
        	nav = GetComponent <NavMeshAgent> ();
    	}


    void Update ()
    {
        
        	//if(EnemyHealth.currentHealth > 0 && playerHealth.currentHealth > 0)
        	//{
           	nav.SetDestination (player.position);
        	//}
        
        	//else
        	//{
           	//nav.enabled = false;
        	//}
		
		if(Time.deltaTime <= timeBetweenAttacks)
		{
			timeBetweenAttacks = timeBetweenAttacks + Time.deltaTime;
			AudioSource audio = GetComponent<AudioSource>();
			audio.clip = laser;
			Instantiate (shot, shotSpawn.position, shotSpawn.rotation);
			Instantiate (shot, shotSpawn.position, shotSpawn.rotation);
			audio.Play();
			

		}
    } 
}
2

The reason for this is that you are increasing timeBetweenAttacks by Time.deltaTime, therefore the next frame it will be equal to Time.deltaTime and fire every frame.
You need a countdown variable like this:

void Update ()
{
         coolDown-= Time.deltaTime

         if(coolDown <= 0)
         {
             coolDown = timeBetweenAttacks;
             AudioSource audio = GetComponent<AudioSource>();
             audio.clip = laser;
             Instantiate (shot, shotSpawn.position, shotSpawn.rotation);
             Instantiate (shot, shotSpawn.position, shotSpawn.rotation);
             audio.Play();
             
 
         }

}