Rapid fire Help

Hi. I am making a game where i heed to hold the space bar down and shoots lots of bullets at once and emit a particle. here is my script feel free to add on to it or leave any useful information. Thanks.(its a java script).

if(Input.GetButtonDown("Jump"))
 	{
 		var bullit = Instantiate
 		
 		(bullitPrefab,GameObject.Find("spawnPoint").transform.position,Quaternion.identity);
 		
 		bullit.tag = "wormProjectile";
 		
 		bullit.rigidbody.AddForce(transform.forward * 2000);
 	}

Read the docs:

GetButton is used for rapid fire. GetButtonDown will only get called once when the button is pressed.