Need to revert to classic Outlook layout

I've dedicated numerous hours to switching back to the classic Outlook layout.

Searches on Google direct me to the top left corner to revert, but there's only a folder list there.

Attempts with settings have been futile. I've even delved into scripts and other numerous methods.

The layout change was unsolicited; it simply appeared one day.

It's exceedingly basic, devoid of links, commands, sidebar, or tools.

I presume it's the Light version.

I'm desperate for assistance; I abhor this bare-bones version. I want all my bells and whistles back.

I'm on macOS 12.7.5.