ArrowSpawner.cs

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

public class ArrowSpawner : StateMachineBehaviour
{
    [SerializeField] GameObject arrowPrefab;
    GameObject arrow;

    public override void OnStateEnter(Animator animator, AnimatorStateInfo stateInfo, int layerIndex)
    {
        if (stateInfo.IsName("shoot"))
        {
            Debug.Log("Spawn Arrow");
            arrow = Instantiate(arrowPrefab,animator.gameObject.transform.position,Quaternion.identity);
        }
    }
}