Is it possible to add_subdirectory() after another target has finished installing ( configure second subdirectory after first subdirectory is finished installing )

thank you, execute process works every time. i also want to add ExternalProject works too but sometimes variables don’t get set when they are passed to the externalproject through CMAKE_ARGS without changing any files and i don’t know of a way to force variables like i would with set( [FORCE]) but for external project so im not sure why that happens.