Transferring one place to another

I didn’t know what other category to put this under so here it is:

I have 3 places in my game. The spawn place where players first spawn in when they join the game and two others. I put some stuff into the spawn but now I want to move it to one of the other places. I’ve tried saving the spawn with all the stuff into a file and opening on the other places, but it just makes it a local copy and an entirely new game. I’ve also tried copying and pasting everything from the spawn place into one of the other places, however, the assets are way too big, and it almost crashes my computer (infinite loading). So how can I transfer or switch the places from one to the other?