(I can only comment on how the USNA system works)
The Candidate Information System (CIS) is the online user-interface for the application and admission process.
If he has already done a preliminary application, then most likely he has a candidate number.
He uses this number (along with his first and last name and the last 4 digits of his SSN) to login to the CIS.
Logging on to the CIS (from the USNA Admissions page
, click on "Continue
") will update him on what he needs to finish, in order to have his application complete.
After logging in, "Application Status" is the first thing on the list.