fgm24/Assets/Scripts/Player/PlayerHP.cs

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

public class PlayerHP : MonoBehaviour
{
    public int maxHealth = 100;
    public int currentHealth;
    public TextMeshProUGUI healthText;
    void Start()
    {
        currentHealth = maxHealth;
    }

    public void Update()
    {
        if (currentHealth <= 0)
        {
            // TODO: Game Over
        }
        if (healthText != null && currentHealth > 0)
        {
            healthText.text = "Health: " + currentHealth;
        }
        else if (healthText != null && currentHealth <= 0)
            healthText.text = "Health: 0";

        if (Input.GetKeyDown(KeyCode.Space))
            TakeDamage(5);
    }

    public void TakeDamage(float damage)
    {
        currentHealth -= (int)damage;
    }
}