Two-Factor Authentication

Can Anyone Help Me With This What Is Two-Factor Authentication? What Is The Use Of It? How To Turn It On? I'm Asking This Because Lichess Have Sent Me Lots Of This Messages

Translation To Spanish
¿Alguien puede ayudarme con esto? ¿Qué es la autenticación de dos factores? ¿Cuál es el uso de ello? ¿Cómo encenderlo? Pregunto esto porque Lichess me ha enviado muchos de estos mensajes.

Japanese
誰かこれを手伝ってくれませんか? 2 要素認証とは何ですか? それの用途は何ですか? オンにする方法は? Lichess が私にこのメッセージをたくさん送ってきたので、これを質問しています。

Norwegian
Kan noen hjelpe meg med dette Hva er tofaktorautentisering? Hva er bruken av det? Hvordan slå den på? Jeg spør om dette fordi Lichess har sendt meg mange av disse meldingene

Two factor authentication adds an extra layer of security to your account. The way it is implemented for Lichess is that in addition to your password you will be asked to enter a code that changes over time. You need to link a device with your account through an app which will generate those codes.

At lichess.org/account/twofactor you can enable two factor authentication, and it also provides a step by step description how to do that.