After you send you application to the CIO, if approved, you get a letter called "assessment letter" containing your file number and instructions to send your full application with the supporting documents to the local visa office within 120 days.
If refused, they send a refusal letter explaining the reasons and confirming the refund.
After you send your full application to the local visa office, they will send you an AOR letter confirming the recipt of your application and containing your new file number and some instructions about the processing of your application.