I have the same question, every single tutorial that I watched (6 and counting in UE4 and UE5) in all of them people only messed with blueprints, and when the night came… boom stars in the sky. I don’t know why people from EPIC removed this and made it harder… but it was a very bad decision.
They didn’t mention in any of those tutorials that I had to enable or download anything.
The 2 best tutorials that I found was the following:
30 Second Setup For Day/Night Cycle In Unreal Engine 5 - YouTube (This one is incredible short and efficient)
Quick & Easy DAY / NIGHT CYCLE for UE5 - YouTube