WhatsApp is adding extra security when you chat from PC

To secure WhatsApp Web and desktop app logins, WhatsApp has added biometric lock support on its mobile app. Until now, you just needed to scan the QR code on your mobile to use WhatsApp Web or the desktop app. Now, if you wish to use WhatsApp from your computer, WhatsApp will ask for Face ID or fingerprint authentication.
This is a welcome step from WhatsApp as it will prevent unknown people from reading your WhatsApp chats from the desktop by just scanning the QR code when your mobile is left unattended or accidentally gets unlocked.
How to use WhatsApp biometric lock feature for WhatsApp Web and desktop app
To log in to WhatsApp on WhatsApp Web, WhatsApp Desktop, or Portal, you need to use your phone to scan the QR code.
-Open WhatsApp on your phone.
-Android: Tap More options.
-iPhone: Go to WhatsApp Settings.
-Tap WhatsApp Web or WhatsApp Web/Desktop.