if one deals with how life originated (creationism) and the other one says nothing at all about the origin of life (evolution) then how has this debate become so great.
I'd say because often the most rabid anti-evolutionists don't understand the theory of evolution, and so they assume it does speak to origins.
But in the creationist's worldview the question of "how did life come to be as it is today?" and the question of "how did life come into existence?" and the question of "how did the Universe get to be as it is now?" and a whole host of other questions are one and the same, with
ipso facto the same answer. I don't find it surprising that they have extreme difficulty understanding that scientists see those as incredibly different questions, and see such great differences that they think it's impossible to conflate their study. The incredible breadth of science requires specialization.