There are two steps to delete a WhatsApp group from your mobile phone as a participant. Firstly go to exit the WhatsApp group, then you will see the option to delete the group after you exit a group or how to delete whatsapp group if not admin.
If you are using WhatsApp on Android phone, here are the steps to do that:
Go to the Chats tab in WhatsApp.
Tap and hold on the group name.
Tap the Trash can icon.
Mute and clear group chat in WhatsApp
Other than exiting a group or delete it from your phone, WhatsApp also provides other options you can manage group chats, such as mute a group chat or delete group chat history. The former allows you to receive WhatsApp messages without the annoying notifications, the later helps users remove group chat history from the phone to reclaim more free storage space.
Save and recover WhatsApp chats
We recommend you to save the WhatsApp chats and files first before you delete the group chat or clear chats and messages. You can follow this guide to save WhatsApp audio, music, voice messages and recordings on Android. If you lost the WhatsApp files and messages without any backups, you should refer to this tutorial to recover deleted WhatsApp messages on Android phone.