So Rory McCrossan gave me this code for an health bar:

But if i whould want to make something that damages the player i dont know how to make a way to do that as some problems like the text not updating and taking more damage than it should take.

let textNode = document. createTextNode("Health: "); document. body. appendChild(textNode);
  let health = 100;
const textNode4 = document.createTextNode(health);
const updateHealthUi = (el, health) => el.textContent = health;

document.body.appendChild(textNode4);

document.addEventListener('keydown', e => {
  e.preventDefault();
  switch (e.key) {
    case "e":
      health = Math.min(100, ++health);
      break;
    case "q":
      health = Math.max(0, --health);
      break;
  }
  updateHealthUi(textNode4, health);})

if you can make a code for the health bar to make it so that i can make a way to take damage pls do