AudioManagerScript.cs

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

public class AudioManagerScript : MonoBehaviour
{
    public AudioSource audioSource;

    public static AudioManagerScript Instance;

    private void Start()
    {

    }

    private void Update()
    {

    }

    private void Awake()
    {
        if (Instance == null)
        {
            Instance = this;
            DontDestroyOnLoad(gameObject);
        }
        else
        {
            Destroy(gameObject);
        }
    }

    public void PlaySFX(AudioClip clip)
    {
        audioSource.PlayOneShot(clip);
    }

    public void ChangeVolume(float volumePercentage)
    {
        audioSource.volume = volumePercentage / 100f;
    }
}