Games Please Fix My Basketball Game

Hi there I am trying to make a first person basketball game. I can't throw my ball and can't start a new round and I am not sure if my problem is in the scripts or the unity editor.

Player.cs

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityStandardAssets.Vehicles.Ball;

public class Player : MonoBehaviour {


public Ball ball;
public GameObject playerCamera;

public float ballDistance = 2f;
public float ballThrowingForce = 5f;

public bool holdingBall = true;

// Use this for initialization
void Start () {
ball.GetComponent<Rigidbody> ().useGravity = false;
}

// Update is called once per frame
void Update () {
if (holdingBall) {
ball.transform.position = playerCamera.transform.position + playerCamera.transform.forward * ballDistance;
if (Input.GetMouseButtonDown(0)) {
ball.ActivateTrail();
holdingBall = false;
ball.GetComponent<Rigidbody>().useGravity = true;
ball.GetComponent<Rigidbody>().AddForce(playerCamera.transform.forward * ballThrowingForce);
}
}
}
}

 

uh..fix it yourself..

it does require, you know.. research, code, testing....what everyone starts with..a blank canvas.

begin with this..

State Machine Basics
The basic idea is that a character is engaged in some particular kind of action at any given time. The actions available will depend on the type of gameplay but typical actions include things like idling, walking, running, jumping, etc. These actions are referred to as states