How to enable two-factor authentication in WhatsApp for Android

Whenever you're setting up WhatsApp on a new phone, you'll have to verify the phone number with a one-time password. WhatsApp also lets you add an extra layer of security in the form of a PIN. Here's how you can set two-factor authentication on your account.

source https://www.androidcentral.com/how-enable-two-factor-authentication-whatsapp-android