public class PlayerHealth : Monobehaviour
{
    [SerializeField]
    Image[] healthContainers;

    int currentHealth;
    int maxHealth;
    int healthPerHealthContainer = 4;

    private void Start()
    {
        maxHealth = healthContainers.Length * healthPerHealthContainer;
        currentHealth = maxHealth;
        UpdateHealthBar();
    }

    public void ChangeHealth(int amount)
    {
        currentHealth = Mathf.Clamp(currentHealth + amount, 0, maxHealth);
        UpdateHealthBar();
    }

    void UpdateHealthBar()
    {
        for (int healthContainerIndex = 0; healthContainerIndex < HealthContainers.Length; healthContainerIndex++)
        {
            healthContainers[healthContainerIndex].fillAmount = Mathf.Clamp01((float)currentHealth / healthPerHealthContainer - healthContainerIndex);
        }
    }

}