Protect your account: password, two-step sign-in, backup email

Open More → Security:

• Two-step sign-in. After your password you also enter a 6-digit code from an authenticator app (or by email). Turn it on at home. The house admin can make it required for everyone who signs in remotely.
• Backup email. A second address that also receives your sign-in codes, in case you lose the first.
• Face ID / fingerprint lock. Locks the app on your phone. It does not change your account.
• Change password. A code is sent to your email to confirm.
• Your devices. More → Profile lists every phone and computer signed in, and you can sign any of them out.

Tip: Use a long password you use nowhere else. A phrase of four random words is strong and easy to remember.