The use of 2FA radically increases the level of security. A person trying to break into a given system must not only know the login and password, but also have access to an additional device owned by the user.
You've probably seen the "Sign in with Google" or "Sign in with Facebook" buttons. You may have used the OAuth authorisation standard if you've used a similar solution.
A PWA (Progressive Web Application) is a type of web application that gives users the experience of using a mobile application
TOTP (Time-Based One-Time Password) is an algorithm that generates one-time passwords based on the current time and a secret key.