If there is a fresh installation of WordPress and WPML, this is not supported.
On the other hand, if WPML’s database was not changed while creating the new website, the association is preserved. There is no way to change the website project to which WPML connects, a new project is created for every new WPML install.
In case it is necessary to have a production and staging website, WPML database should be copied from one to the other. Then, they will be associated to the same project.