Why is this spawning the bullets in the center of the game world?

It is spawning it in the center of the world not where the position the weapon is.
Also how do I make this into an actual gun.

public void FireStuff(GameObject prefab){
		GameObject FatBut = prefab;
		if (Timer >= TimeEnd) {
			for (int i = 0; i < Bullets; i++) {
				
				Vector3 firingPoint = new Vector3 (FiringPoints <em>.localPosition.x, FiringPoints _.localPosition.y, FiringPoints *.localPosition.z);*_</em>

* Instantiate (FatBut, firingPoint, transform.rotation);*

* }*
* Timer = 0;*
* }*
* }*
}

Probably because you’re using the local position of the diring point (relative to whatever its parent is). You should use the position instead:

Vector3 firingPoint = new Vector3 (FiringPoints <em>.position.x, FiringPoints _.position.y, FiringPoints *.position.z);*_</em>

or, more simply:
Vector3 firingPoint = FiringPoints*.position;*