In the movie Life (2017), Calvin is outside the space station. Calvin is shown to be an organic life-form that is Carbon based. They mention that it needs food, oxygen, and a suitable temperature to survive. Outerspace has none of these. Yet, Calvin is shown to comfortably move around outside the ship and survive. The same Calvin goes into a dormant state earlier in the film when there is an atmospheric accident. What's the deal here? How is it able to breathe outside the space station?
We don't know whether Calvin is actually "comfortable" outside, or desperately fighting for its life on quickly depleting oxygen reserves - the latter could be an in-universe explanation.
But realistically, you're right, it does not make much sense. If Calvin can survive for several minutes without any atmosphere at all, then a slight drop in pressure or oxygen content (which still allows humans to survive) should be no problem, as opposed to making Calvin stupidly follow a trail of "oxygen torches" (whatever that's supposed to be).
As a review I read put it quit aptly: "Life" is a pretty good horror movie, but a pretty weak science fiction story.