how to write English name

What is First Name, Last Name? How to enter First Name, Last Name correctly

What is First Name, Last Name? How to enter First Name, Last Name correctly

Nowadays, the demand of using foreign websites and applications is increasing, we must enter First Name, Last Name for the first time to create an account or login. So what are First Name, Last Name? How to distinguish it? How to write the name in English or fill in the form correctly?