We humans stand out among currently living species as being the only ones with a developed imagination. We alone are able to dream of things that do not exist. Some other species get tantalizingly close, like gorillas and some birds, but it is always a bit disappointing to see how limited they are.
There have been some shrines found dating back nearly a million years (well before Homo sapiens), but their purpose is completely unknown.
Anyway, asking what it would look like is meaningless. That's like asking what the best seller would be if octopi could write books. 4's quote about how a gorilla interprets death is the the most you can say. Chimps don't have the physical capacity for religion.