What you may have to do, for instance if you’re thinking of something like Skyrim and you want entirely different levels, loading screens and whatnot, is save a few values. Like with your day/night cycle, whenever you open a level, like an interaction with a door opening an entirely new level, you have to run a function to save the values, like your sun height and your time of day if you have that, or a day of the week if you have that. Once you begin playing that new level you should load the save file that you use, and if you have a function previously set up not in the level blueprint, just a blueprint for your day/night cycle, include a section for it to read the save file and replace certain values, again like your sun height, and then set its current sun height. That will make it so that whatever level uses your day/night cycle blueprint will have to read the file once you begin playing, and then save back to that file one you’re switching levels. It also makes it fairly easy if you’re going to have a big save game function and need to save your location and plenty of information like quests, so every time you load into a save game the values aren’t reset to the base values in your coding.