Is there a way to use 2FA
Also how can I make sure if two people cant login to the same account and over ride each other files
What do you mean by "2FA"?
About the second question, you can set the constant define CLEAR_PLAYER_SESSIONS to TRUE in your /lib/config.php to delete all sessions of an authenticated user after a successful login. This way all requests coming from the "other" client for the same user will be invalidated and cancelled, for example: you login on a PC, then login again with the same account on another PC (or the same PC but launch a second instance), upon the second instance login it will delete the older sessions and so every call from the first instance will fail.
FRANCESCO CROCETTI @ SKARED CREATIONS
2FA = Two-factor authentication
There's no built-in two-factor authentication implemented, but if you already have a library to handle the code generation and verification on-the-fly then it's pretty easy to integrate, that is just matter of generating after successful call to Authenticate and checking the generated code in the UI.
FRANCESCO CROCETTI @ SKARED CREATIONS