Problem of syncing

Hey guys,

I have just started learning on the UEFN program. I am facing a problem, which is that when I make changes to the map in the program, I do not see the changes in the Creative mod, please help me

for example, if i put an car in my map in UEFN then i save all changes then i opend the game creative mod the map still with no changes ( there is no car )

Thanks