Did Buddha take an opium to gain his enlightenment?

No, and it won't help you to. The Buddha gained Enlightenment after practicing severe austeries (denying himself all comforts, even food). Then he realized that punishing oneself is as self-defeating as indulging in excessive pleasures, since both approaches tie one's conscienceness to the physical state. He then began to eat reasonably, sleep sensibly, take exercise and rest in measure and meditate sincerely without making a fetish of it.