If you’re spending time looking and wondering that you always need to go to the app switcher to go the Settings from the Unified Interface, you need to do the following –
Once you are in the Unified Interface, click on the Gear icon next to the help icon on top-right corner as shown below and click Advanced Settings –
Right on the next tab, Settings with the classic UI is shown –
And there’s nothing else on the SiteMap.
Hope this helps!