First and foremost, the only way to get out of a group chat is by deleting your account. This is not something you can do on the app itself. If you want to leave the group, simply delete your account. If you leave the group, you can rejoin it at any time by creating a new account. Unfortunately, WhatsApp doesn’t let you delete groups that you’re a part of. However, you can leave the group and then add yourself back in, but you will only be able to send messages to the group owner. You can’t delete your messages from the group. You can, however, delete messages from your own phone once you’ve read them. This can be done by unchecking the box in the app’s messaging screen.