What does a fossil tell us? Something died, does not tell us whether it had
offspring or different off spring.
A single fossil can tell us a bit about the physiology of an individual creature that lived and died some time ago; dating methods can even tell us when it lived and died.
Multiple bones or a complete or partial skeleton from the same animal can tell us even more: a closer-to-complete physiology of the animal, which can tell us the animal's size, how it moved, what it ate, etc... as you gather more and more data, you get closer to the level of information you could gather by studying a living animal.
Fossils from many different animals in the same species can tell us the range of the species (both geographically and temporally), tell us more about how the animal lived (did they live alone or in packs? Did they lay their eggs and leave, or did they rear their young? Did they migrate?) and provide more data for the sorts of things I mentioned above.
Fossils from many different species can help us understand how the species related to each other: which ones were predators, which ones were prey, which ones competed against each other, and which ones are descended from which other ones.
Also, context is very important;
where a fossil is found can give information as well. I remember a line in a Steven Jay Gould book where he quoted the geologist who trained the Apollo astronauts on how to take soil and rock samples: "If you bring me a dead cat, all I can tell you is that it's a cat and it's dead. But if you tell me that you found it at the side of the highway, I'll reach a completely different set of conclusions than if you tell me you found it in the kitchen of your favourite restaurant."
Really, saying "what's the point of collecting fossils to learn about the history of life?" is a lot like saying "what's the point of collecting evidence to learn about a crime?" Fossils can tell us a lot.