Dear Karen Matelan,
Good morning! Thank you for posting in the Microsoft Community. We will be happy to help you.
I'm so sorry hear that you do not like the new Outlook. I deeply understand the inconvenience caused and apologize for it.
Just adding some visuals for clarity. You can Toggle out of the new Outlook at the top right of the new Outlook window.

Also, kindly find the following article for more details regarding this: Toggling out of the new Outlook for Windows preview - Microsoft Support
Please let me know if you encounter any issues in the process or if you have any further questions.
I appreciate your patience and understanding and thank you for your time and cooperation.
Sincerely
Ralph Chawatama | Microsoft Community Moderator