Life in Sparta seems like something out of a fantasy book rather than a real ancient civilization, and I feel as though such a state could never exist (or at least, couldn't exist for as long as Sparta did), even in modern times.
Nope.
To save u/Iphikrates the trouble, I'll post this neat Index of Spurious Spartan Superiority
If you still have further questions, feel free to ask them here or in the threads I linked, most of whom are rather recent (i.e. the last 2 days) but I expect the answers there should give you plenty to go on.
This has been covered many times.
Here is one to get you started:
I read a few of the topics. Instead of starting with recommandations of modern books, you could start with Plutarch's Life of Lycurgus. (One of the many Lives that would probably interest you). It's gonna give you a good idea ( and far from "mythical") of how Sparta became The very peculiar city that it was.