If you choose to remove yourself from WhatsApp, here’s what you’ll want to do:
To export your messages, tap on the chat you want to save. Tap on the name of the chat at the top and scroll down to “Export Chat,” and then choose whether or not you want to include the media from the chat with it.
Then request your account data by going to “Settings” in the bottom right corner. Then choose “Account” and “Request Account Info”. It will take about three days to receive your data report from WhatsApp, but they’ll notify you when it’s ready.
WhatsApp’s long-awaited disappearing messages feature has finally rolled out for all users, but you should make sure you’re comfortable with how the feature works before using it.Read more
Finally, to delete your account, go to “Settings,” then “Account,” and “Delete My Account”. Doing so will erase your message history, remove you from all groups, and delete your backup. Now you’re free and clear of WhatsApp, and just need to convince your friends and family to migrate to a different app.