Enemy.cs

using UnityEngine;

public class Enemy : MonoBehaviour
{
    public float health; // keep the health of the enemey

    [HideInInspector]
    public Vector2 direction; // direction where the enemy is now facing.

    public GameObject bullet; // Bullet object what the enemy is gonna shoot. 
    
    public float shootSpeed = 10; // how fast the bullet will be
    

    public void Shoot(Vector2 shootPosition, Vector2 direction)
    {
        // clone the bullet
        GameObject bulletObj = Instantiate(bullet, shootPosition, Quaternion.identity);
        
        // add force to the bullet. 
        bulletObj.GetComponent<Rigidbody2D>().AddForce(direction * shootSpeed,ForceMode2D.Force);
    }
}