Our first step will be to add our variables needed for the health bar:

public float currentHealth = 100;
public float maximumHealth = 100;
float currentBarLength;
public Transform HealthBar;
Vector3 OrigScale;

The first three variables are what we'll use to calculate our health bar. The Transform variable is how we'll interact with our 3D object that's being used as our health bar. The Vector3 variable is a reference point for when we scale the bar.

Our next step will be to add a Start() function. We'll use the Start() function to set the OrigScale variable:

void Start()
{
  OrigScale = HealthBar.transform.localScale;
}

We set OrigScale before we do anything else in the health bar. This is what we'll use as a reference point for the health bar. Next, we'll create our Update() function:

void Update()
{
  currentBarLength = currentHealth...