Install and Sign-Up for the latest beta version of WhatsApp on both devices.
Log in and click on the three dots menu displayed on the top right corner of the app.
Click on the ‘Link a Device’ option in companion mode to get a QR code.
Open WhatsApp on your secondary device and go to Linked Devices.
Scan the QR code being shown on the primary device.
Your WhatsApp account will now be linked on both devices once the chats are synced.