How to organize information hiding during file input/output?

Question

C++ / C#

Good time of the day.
When creating programs (even the smallest ones), it often becomes necessary to use files, both for storing service information and for storing user information. I would like to avoid user contact with files (even if the files contain user information, for example, something like a database), and organize his work only through the program interface.
How to achieve this?

Answer 1

For windows, alternative streams can be used, not very secure, but can be used in conjunction with encryption