in the photos you see all the information you need, what have i done wrong?
please help me answering this question.
Like @Harinezumi said you must create a IEnumerator function to use WaitForSeconds:
void Start ()
{
StartCoroutine(MyCoroutine());
}
IEnumerator MyCoroutine()
{
while (true)
{
//Put here your script that you have in Update()
}
}