Hi! So im making my round system for a murder mystery game and im wondering if theres a way to wait until the map loads. Im aware of content provider and PreloadAsync but i do not know if those are good options for what i want. Would like some help! 
The maps are structured inside folders, like this:
All you can do is paste it onto the workspace, and WaitForChild to try and do the job.
If you have StreamingEnabled turned on, it’s possible to reliably wait until the entire map (including all of its descendants) have loaded in.
By converting the upper-most folder into a Model (which would be the “Barn” folder in the screenshot you posted) you can set its ModelStreamingMode to Atomic, which will ensure that the Model is only replicated / can only be referenced once all of its descendants have been streamed in.
This way, you would only need one :WaitForChild() call on the Model without needing to have additional calls on the existing Spawns and anything else that was part of the Model at that time.
*Disclaimer: If I understand correctly, for super large maps that cannot realistically be streamed in all at once, setting the ModelStreamingMode to Atomic may cause the model to never be streamed in to the player.