Can i use IEnumerator as Update func?

float speed = 0.01f; 
float time = 0;
while ( time < 1)
{
    time += speed;
    //Rest of code
}

image.color = Color.Lerp(image.color, _color, time);

public float speed = 0.01f; //The speed at which the fade happens

private Image[] imageComponents;
private Text[] textComponents;

void Start()
{
    imageComponents = gameObject.GetComponentsInChildren<Image>(); //Cache the images so we don't have to find them every time
    textComponents = gameObject.GetComponentsInChildren<Text>(); //Cache the texts

    StartCoroutine(HideAllBoosters());//Start the Coroutine
}

IEnumerator HideAllBoosters()
{
    float t = 0; //Start value for our loop
    while (t < 1) // 1 indicates the max value of t at which the loop stops. In this case after 100 iterations since the speed is 0.01
    {
        t += speed;

        foreach (Image image in imageComponents)
        {
            Color _color = image.color;
            _color = new Color(_color.r, _color.g, _color.b, 0);
            image.color = Color.Lerp(image.color, _color, t); //t dictates how far in the interpolation we are.
        }
        foreach (Text text in textComponents)
        {
            Color _color = text.color;
            _color = new Color(_color.r, _color.g, _color.b, 0);
            text.color = Color.Lerp(text.color, _color, t);
        }
        yield return null;
    }
}

Color _color = image.GetComponent<Image>().color;

Color _color = image.color;