remember username and password

it so that it remember for Example i am makeing an os and i now how to make a username and password locking system but i am makeing one where they choose the username and password they want inside the program how do i make it so that it remember for Example password = test the problem is when the computer turns off and back on it will not remember that password = test.

It took me a while to read what you actually wanted. Please try to format sentences next time to make yourself more understandable.

You want to save the username and password in a file. On how to do that, you can check this tutorial

However, it is not save to store the password in plain text, use this hashing function to make your OS more secure.

just save the configuration into a file, and then load the file on startup :D/>