Hi,
If i get your question correctly, then this is the default behavior of AEM, we used to create and store content in author instance, then replicate this content to multiple publish instance using replication agents.
If you have multiple author instance and want to use only one instance for creating content then that is also possible but it will increase load on single author instance as now it has to replicate content to publish also and other author environments also.
Let me know does if you get your answer or you are trying to point something else.
regards,
Ankur