We do recommend to transfer a Workspace to another Owner user, before you delete the Root user, otherwise you will lose everything.
You can either leave a Workspace (as a not Root user) or you can delete a Workspace (as a Root user) and then delete an account. Remember deleting an account is a permanent solution.
Go to the Workspace
Select Workspace Settings
Click on Leave Workspace or Delete Workspace
Fill in the phrase
Click on leave workspace
Click on Delete My Account (This option only shows if you don't have any workspaces)
Click on Close My Account
Your account has been successfully deleted.