player movement

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class PlayerMovement2 : MonoBehaviour
{
    public Animator animation;
    public float velocity = 20f;

    [Range(1f, 100f)]
    public float jumpVelocity;

    Transform playerGraphics;

    bool isOnGround = false;

    public AudioClip jump;
    private AudioSource audioSource;

    private void Awake()
    {
        playerGraphics = transform.Find("Player GFX");  // Used to split the player GFX from his arms or guns GFX
    }

    public void Start()
    {
        audioSource = GetComponent<AudioSource>(); // Footsteps Audio
    }

    public void Update()
    {
        // Movement
        Vector3 movement = new Vector3(Input.GetAxis("Horizontal"), 0f, 0f);
        transform.position += movement * Time.deltaTime * velocity;

        //Audio
        if (Input.GetAxis("Horizontal") == 0)
        {
            audioSource.Play();
        }
        if (Input.GetButtonDown("Jump") && isOnGround == true)
        {
            audioSource.PlayOneShot(jump);
        }

        // Animation
        if (Input.GetAxis("Horizontal") != 0)
        {
            animation.SetFloat("Speed", velocity);
        }
        else
        {
            animation.SetFloat("Speed", 0f);
        }

        // Jump
        if (Input.GetButtonDown("Jump") && isOnGround == true)
        {
            GetComponent<Rigidbody2D>().velocity = Vector2.up * jumpVelocity;
        }

        // Sprite Flip
        Vector3 potatoPunch = playerGraphics.localScale;
        if (Input.GetAxis("Horizontal") < 0)
        {
            potatoPunch.x = -1;
        }
        else if (Input.GetAxis("Horizontal") > 0)
        {
            potatoPunch.x = 1;
        }
        playerGraphics.localScale = potatoPunch;
    }

    // Jump Detection
    public void OnCollisionEnter2D(Collision2D collision)
    {
        if (collision.collider.tag == "Ground")
        {
            audioSource.Play(); //Audio continues on entering ground collision after jumping for walking
            isOnGround = true;
        }

        Debug.Log("Enter");
    }
    private void OnCollisionExit2D(Collision2D collision)
    {
        if (collision.collider.tag == "Ground")
        {
            audioSource.Stop(); //Audio stop on exiting ground collision for walking
            isOnGround = false;
        }

        Debug.Log("Exit");
    }
}