Open WhatsApp
Go to Settings
Tap Chats
Tap Chat backup
Choose Back Up Now
Select Google Account or iCloud account if prompted
Turn on Include Videos if desired
Set up automatic backup frequency if available
Make sure you are connected to Wi-Fi
Ensure enough storage is available on your phone and cloud account
Wait for the backup to complete
Verify the last backup date and time
On a new phone, install WhatsApp
Verify the same phone number
Restore the backup when prompted