Let's say I have made 20 scenes in a world, with enemies and objects and coins and I simply want to copy all those 20 scenes and only change the background. Is there anyway to do such a thing or am I limited to only duplicate one scene at a time?
I don't think this will be possible until BuildBox has multi-select (coming in BuildBox 3, some time next year)
Multi-select is already part of 2.3. No need to wait for Buildbox 3. You could copy the entire world which copies as well all scenes in it. But if you want to copy all scenes within the same world, then yes, the only option (even in 2.3) is to copy them one by one.