unity after 1 second code example

Example 1: Time delay C# unity

void start()
StartCoroutine(Text());

IEnumerator Text()  //  <-  its a standalone method
{
	Debug.Log("Hello")
    yield return new WaitForSeconds(3)
    Debug.Log("ByeBye")
}

Example 2: unity3d coroutine to do for n seconds

StartCoroutine(GoLeft()); 
 
IEnumerator GoLeft() {     
float timePassed = 0;     
    while (timePassed < 3){

    timePassed += Time.deltaTime;
    yield return null;     
    } 
}