First, go to Settings > General. At the bottom of the page, you’ll find the option to "Delete workspace":
This action is irreversible, and will delete all of your data. If you have any data you need to keep, make sure to export any necessary data before deleting your workspace.
If you have further questions, you can reach out in the Messenger, or, we also have a dedicated Data Protection Officer to help you with any requests or questions you have about your data. You can reach out by email, to dataprotection@intercom.io.