Things are quite complicated when it comes to higher entities in Neil Gaiman's Sandman.
The role of the Endless in The Sandman — both in the graphic novel and Netflix's TV adaptation — is massive, as they are technically the ones who maintain the order of things in the universe. However, many fans, especially those who are new to the fandom, wonder what kind of relationship do they have with God.
First of all, was God the one to create the Endless? If he is the creator of the universe, it's only natural to suggest that the answer to the question is yes. However, it's not that simple.
According to the canon, the Endless siblings have parents: Mother Night and Father Time. It's unclear who created them and whether it was Presence — the character who is essentially God in Gaiman's universe. We do know that Presence is the father to Lucifer and Michael, but the extent of his relation to Time and Night, as well as their kids, is unknown.
There is also a theory (which is even confirmed by Lucifer in the comics, although it might be just the character's vision) that the Endless are essentially "side effects" of the way the creator made the universe. For instance, Death is the result of him making life finite, and Destiny exists because he has a plan.
Gaiman never directly implied that the Endless were created by God. However, there are many hints in the comics that he did, after all. It's also quite clear that the concepts of heaven and hell are not just words in Gaiman's universe: even in the Netflix's adaptation, Dream himself traveled to hell to collect his power tools.
The Sandman is currently awaiting a green light from Netflix to start working on a second season — something that some fans fear might not happen given the prolonged silence from the network about the project's future.
The Sandman Season 1 is currently streaming on Netflix, having spent more than six weeks in the global top 10.