Top down rotation using mouse (Two Options 1. Fix my code 2. find a way to have 3D walls

So basicaly what iam trying to do is create a top down shooter which use the mouse to aim. However my code does not work the way

the code

using System.Collections;
using System.Collections.Generic;
using Mono.Cecil.Cil;
using UnityEngine;
using UnityEngine.UIElements;

public class Goon : MonoBehaviour
{
[Header(“Gun Settings”)]
public Transform Gun;
public Transform RougeLikeParentPlayer;
public PlayerMovement RougeLikeParentPlayer_Movement;
public float FireRate = 0.1f;
public int clipSize = 30;
public int ReservedAmmoCapacity = 270;

[Header("Gun Variables")]
public bool _Equipeded = false;
public bool _AutoAim;
public bool _FullAuto;
public bool _canShoot;
public int _Damage;
public int _CurrentAmmoInClip;
public int _AmmoInReserve;
public float _Knockback;
public LayerMask EnemyMask;

[Header("Shoot")]
public KeyCode ShootKey = KeyCode.Mouse1;
public GameObject Bullet;
public Bullet BulletScript;
public GameObject BulletPrefab;
public GameObject ShootPoint;
public float BulletSpeed = 1.5f;

[Header("Aim")]
public Rigidbody2D Rb;
public Transform Enemy;
public bool FacingRight = true;
public float RotationZ;
public bool DoNotCallUntilFinished = false;

// Start is called before the first frame update
void Start()
{
    Rb = this.GetComponent<Rigidbody2D>();
    RougeLikeParentPlayer_Movement = RougeLikeParentPlayer.GetComponent<PlayerMovement>();
}

// Update is called once per frame
void FixedUpdate()
{
    if (_Equipeded == true)
    {
        if (_AutoAim == true)
        {

        }
        else if (_AutoAim == false)
        {
            Vector3 MousePos = Camera.main.ScreenToWorldPoint(Input.mousePosition);

            Vector3 Direction = MousePos - transform.position;
            Direction.Normalize();

            RotationZ = Mathf.Atan2(Direction.y, Direction.x) * Mathf.Rad2Deg;

            if (!FacingRight)
            {
                transform.localRotation = Quaternion.Euler(0, 0, RotationZ);
            }
            else if (FacingRight)
            {
                transform.localRotation = Quaternion.Euler(0, 0, -RotationZ - 180);
            }

            if (MousePos.x < RougeLikeParentPlayer.position.x && !FacingRight)
            {
                Flip();
            }
            else if (MousePos.x > RougeLikeParentPlayer.position.x && FacingRight)
            {
                Flip();
            }
        }

        if (_canShoot == true)
        {
            if (_FullAuto == false && Input.GetKeyDown(ShootKey))
            {
                Bullet = Instantiate(BulletPrefab, ShootPoint.transform.position, transform.rotation);
                BulletScript = Bullet.GetComponent<Bullet>();
                BulletScript.Shooter = Rb;
                BulletScript.BulletSpeed = BulletSpeed;
            }
            if (_FullAuto == true && Input.GetKey(ShootKey))
            {
                StartCoroutine(Shoot());
            }
        }
    }
}

IEnumerator Shoot()
{
    _canShoot = false;
    yield return new WaitForSeconds(FireRate);
    Bullet = Instantiate(BulletPrefab, ShootPoint.transform.position, transform.rotation);
    BulletScript = Bullet.GetComponent<Bullet>();
    BulletScript.Shooter = Rb;
    BulletScript.BulletSpeed = BulletSpeed;
    _canShoot = true;
}

int i;

void Flip()
{
    i++;

    Debug.Log("Flip " + i);

    FacingRight = !FacingRight;
    DoNotCallUntilFinished = false;

    RougeLikeParentPlayer_Movement.CalledFromObject = this.gameObject;
    RougeLikeParentPlayer_Movement.PlayerDirection();
}

IEnumerator Delay(float Delay, bool DelayBool)
{
    yield return new WaitForSeconds(Delay);
    DelayBool = false;
}

}

I know the issue of the code but i cant fix it. I Currently have my camera set to persecutive not orthographic which causes the gun not to rotate. there are two ways to solve this but I am not sure on how to execute them i
A have to find a way to deal with the Extra value
or
B need to find a way to make my walls look 3d using orthographic (i believe shaders?)
plz help Ive been on this for two weeks now

okay so ive recreated my code however there is still one problem [Header(“Gun Settings”)]
public Transform Gun;
public Transform RougeLikeParentPlayer;
public PlayerMovement RougeLikeParentPlayer_Movement;
public float FireRate = 0.1f;
public int clipSize = 30;
public int ReservedAmmoCapacity = 270;

[Header("Gun Variables")]
public bool _Equipeded = false;
public bool _AutoAim;
public bool _FullAuto;
public bool _canShoot;
public int _Damage;
public int _CurrentAmmoInClip;
public int _AmmoInReserve;
public float _Knockback;
public LayerMask EnemyMask;

[Header("Shoot")]
public KeyCode ShootKey = KeyCode.Mouse1;
public GameObject Bullet;
public Bullet BulletScript;
public GameObject BulletPrefab;
public GameObject ShootPoint;
public float BulletSpeed = 1.5f;

[Header("Aim")]
public Rigidbody2D Rb;
public Transform Enemy;
public bool FacingRight = true;
public float RotationZ;
public bool DoNotCallUntilFinished = false;
public Camera OthoCam;

// Start is called before the first frame update
void Start()
{
    Rb = this.GetComponent<Rigidbody2D>();
    RougeLikeParentPlayer_Movement = RougeLikeParentPlayer.GetComponent<PlayerMovement>();
}

// Update is called once per frame
void FixedUpdate()
{
    if (_Equipeded == true)
    {
        if (_AutoAim == true)
        {

        }
        else if (_AutoAim == false)
        {
            Vector3 MousePos = new Vector3(Input.mousePosition.x, Input.mousePosition.y, Camera.main.nearClipPlane);

            MousePos = Camera.main.ScreenToWorldPoint(MousePos);

            Debug.Log(MousePos);

            Ray CamRay = Camera.main.ScreenPointToRay(MousePos);
            Plane GroundPlane = new Plane(Vector3.forward, Vector3.zero);
            float RayLength;

            if (GroundPlane.Raycast(CamRay, out RayLength))
            {
                Vector3 PointToLook = CamRay.GetPoint(RayLength);
                Debug.DrawLine(CamRay.origin, PointToLook, Color.blue);

                RotationZ = (Mathf.Atan2(PointToLook.x, PointToLook.y) * Mathf.Rad2Deg) + 90;

                Debug.Log(RotationZ);

                if (FacingRight)
                {
                    transform.localRotation = Quaternion.Euler(0, 0, RotationZ);
                }
                else if (!FacingRight)
                {
                    transform.localRotation = Quaternion.Euler(0, 0, -RotationZ - 180);
                }
            }

            if (MousePos.x < RougeLikeParentPlayer.position.x && !FacingRight)
            {
                Flip();
            }
            else if (MousePos.x > RougeLikeParentPlayer.position.x && FacingRight)
            {
                Flip();
            }
        }

        if (_canShoot == true)
        {
            if (_FullAuto == false && Input.GetKeyDown(ShootKey))
            {
                Bullet = Instantiate(BulletPrefab, ShootPoint.transform.position, transform.rotation);
                BulletScript = Bullet.GetComponent<Bullet>();
                BulletScript.Shooter = Rb;
                BulletScript.BulletSpeed = BulletSpeed;
            }
            if (_FullAuto == true && Input.GetKey(ShootKey))
            {
                StartCoroutine(Shoot());
            }
        }
    }
}

IEnumerator Shoot()
{
    _canShoot = false;
    yield return new WaitForSeconds(FireRate);
    Bullet = Instantiate(BulletPrefab, ShootPoint.transform.position, transform.rotation);
    BulletScript = Bullet.GetComponent<Bullet>();
    BulletScript.Shooter = Rb;
    BulletScript.BulletSpeed = BulletSpeed;
    _canShoot = true;
}

int i;

void Flip()
{
    i++;

    Debug.Log("Flip " + i);

    FacingRight = !FacingRight;
    DoNotCallUntilFinished = false;

    RougeLikeParentPlayer_Movement.CalledFromObject = this.gameObject;
    RougeLikeParentPlayer_Movement.PlayerDirection();
}

IEnumerator Delay(float Delay, bool DelayBool)
{
    yield return new WaitForSeconds(Delay);
    DelayBool = false;
}

}

the only problem is that if i leave my mouse idle and then move the mouse position does not up date and stays as the old mouse position until i move my mouse but then its still moving from the old position for example i stop moving my mouse at (5,18,8) so i move my character down by five so now the mouse pos should be (5,13,8) but it stays as (5,18,8) then say i move my mouse right by five instead of being (10,13,8) its (10,18,8). i believe this is because it is not to world point? even thought i do use screen to world point as well as the fact that it does not constantly update? only when the mouse is moved by the user?