"These beds are not from water," doesn't make sense in English (yes, I reported it); I assume the meaning is "...are not made from water" or "...are not made out of water."

couldn't it refer to water beds? you know, water filled matresses?

I believe "-ből" can idiomatically mean "made of", so this means "No, these beds are not water beds." Or more succinctly and given the context that "these" refers to bed, "These are not water beds."

No, this sentence is not useful. And if it’s the subject of debate as to its meaning it’s not teaching us anything either