I want the bullet to shoot at the center of the screen

using UnityEngine;
using TMPro;

public class ProjectileGun : MonoBehaviour
{
    public bool shootingEnabled = true;

    [Header("Attatch your bullet prefab")]
    public GameObject bullet;

    //Gun stats
    public float shootForce, upwardForce;
    public float timeBetweenShooting, spread, reloadTime, timeBetweenShots;
    public int magazineSize, bulletsPerTap;
    public bool allowButtonHold;
    int bulletsLeft, bulletsShot;

    //recoil
    public Rigidbody playerRb;
    public float recoilForce;

    //some bools
    bool shooting, readyToShoot, reloading;

    public Camera fpsCam;
    public GameObject muzzleFlash;
    public Transform attackPoint;

    //Show bullet amount
    //public CamShake camShake;
    //public float camShakeMagnitude, camShakeDuration;
    public TextMeshProUGUI text;

    public bool allowInvoke = true;

    private void Start()
    {
        bulletsLeft = magazineSize;
        readyToShoot = true;
    }
    void Update()
    {
        MyInput();

        //Set Text
        text.SetText(bulletsLeft / bulletsPerTap + " / " + magazineSize / bulletsPerTap);
    }
    private void MyInput()
    {
        //Input
        if (allowButtonHold) shooting = Input.GetKey(KeyCode.Mouse0);
        else shooting = Input.GetKeyDown(KeyCode.Mouse0);

        if (Input.GetKeyDown(KeyCode.R) && bulletsLeft < magazineSize && !reloading) Reload();

        //Shoot
        if (readyToShoot && shooting && !reloading && bulletsLeft > 0){
            bulletsShot = bulletsPerTap;
            Shoot(); //Function has to be after bulletsShot = bulletsPerTap
        }
    }
    private void Shoot()
    {
        if (!shootingEnabled) return;

        readyToShoot = false;

        //Find the hit position using a raycast
        Ray ray = fpsCam.ViewportPointToRay(new Vector3(0.5f, 0.5f, 0));
        RaycastHit hit;
        //Check if the ray hits something
        Vector3 targetPoint;
        if (Physics.Raycast(ray, out hit))
            targetPoint = hit.point;
        else
            targetPoint = ray.GetPoint(75);

        //Calculate direction
        Vector3 directionWithoutSpread = targetPoint - attackPoint.position;

        //Spread
        float x = Random.Range(-spread, spread);
        float y = Random.Range(-spread, spread);
        float z = Random.Range(-spread, spread);

        //Calc Direction with Spread
        Vector3 directionWithSpread = directionWithoutSpread + new Vector3(x, y, z);

        //Instantiate bullet/projectile
        GameObject currentBullet = Instantiate(bullet, attackPoint.position, Quaternion.identity);
        currentBullet.transform.forward = directionWithSpread.normalized;

        //AddForce
        currentBullet.GetComponent<Rigidbody>().AddForce(directionWithSpread.normalized * shootForce, ForceMode.Impulse);
        currentBullet.GetComponent<Rigidbody>().AddForce(fpsCam.transform.up * upwardForce, ForceMode.Impulse);
        //Activate bullet
        if (currentBullet.GetComponent<CustomProjectiles>()) currentBullet.GetComponent<CustomProjectiles>().activated = true;

        Instantiate(muzzleFlash, attackPoint.position, Quaternion.identity);

        //Shake Camera
        //camShake.StartCoroutine(camShake.Shake(camShakeDuration, camShakeMagnitude));

        bulletsLeft--;
        bulletsShot--;

        if (allowInvoke)
        {
            Invoke("ShotReset", timeBetweenShooting);
            allowInvoke = false;

            //Add recoil force to player (should only be called once)
            playerRb.AddForce(-directionWithSpread.normalized * recoilForce, ForceMode.Impulse);
        }

        if (bulletsShot > 0 && bulletsLeft > 0)
            Invoke("Shoot", timeBetweenShots);
    }
    private void ShotReset()
    {
        readyToShoot = true;
        allowInvoke = true;
    }
    private void Reload()
    {
        reloading = true;

        Invoke("ReloadingFinished", reloadTime);
    }
    private void ReloadingFinished()
    {
        bulletsLeft = magazineSize;
        reloading = false;
    }

    #region Setters

    public void SetShootForce(float v)
    {
        shootForce = v;
    }
    public void SetUpwardForce(float v)
    {
        upwardForce = v;
    }
    public void SetFireRate(float v)
    {
        float _v = 2 / v;
        timeBetweenShooting = _v;
    }
    public void SetSpread(float v)
    {
        spread = v;
    }
    public void SetMagazinSize (float v)
    {
        int _v = Mathf.RoundToInt(v);
        magazineSize = _v;
    }
    public void SetBulletsPerTap(float v)
    {
        int _v = Mathf.RoundToInt(v);
        bulletsPerTap = _v;
    }

    #endregion
}

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Ok thank you I will repost it now

Excellent.

To help gain more insight into your problem, I recommend liberally sprinkling Debug.Log() statements through your code to display information in realtime.

Doing this should help you answer these types of questions:

  • is this code even running? which parts are running? how often does it run? what order does it run in?
  • what are the values of the variables involved? Are they initialized? Are the values reasonable?
  • are you meeting ALL the requirements to receive callbacks such as triggers / colliders (review the documentation)

Knowing this information will help you reason about the behavior you are seeing.

You can also put in Debug.Break() to pause the Editor when certain interesting pieces of code run, and then study the scene

You could also just display various important quantities in UI Text elements to watch them change as you play the game.

If you are running a mobile device you can also view the console output. Google for how on your particular mobile target.

Here’s an example of putting in a laser-focused Debug.Log() and how that can save you a TON of time wallowing around speculating what might be going wrong:

https://discussions.unity.com/t/839300/3