To activate two-factor authentication, go to your Account page and turn on the Two-factor authentication toggle under Security.
P.S. If you're using FTP or WebDAV while 2FA is enabled, you will need to log in using a combination of your password followed immediately by the one-time password from your authenticator app - with no blank space between them. It should look like this: passwordonetimepassword.
Recovery
Once 2FA is enabled, we'll provide you with recovery codes. They are important if you ever lose access to your authenticator app. Don't lose these codes; you may need them to regain access to your account.