Hello Sir Abraham
Welcome to Microsoft Community.
Based on your description, I understand that you have encountered the problem of deleting a group.
The link you queried clearly states that this article is applicable to administrators of company or enterprise accounts.
For this reason, I would like to confirm what URL you use when logging in to Outlook Online? outlook.office.com ? outlook.com ?
Are you the owner of the current group?
For ordinary Microsoft personal accounts, such as @outlook.com /@hotmail.com accounts, you need to check whether you are the owner of the current group. Only the owner can edit and delete the group. If you are only a member of the group, you can click Leave Group to make the group no longer appear under your account.
I hope this information has been helpful to you. If you have any questions, please let me know and I will be happy to help.
Sincere greetings
Forry.F - MSFT | Microsoft Community Support Specialist