A family of Microsoft word processing software products for creating web, email, and print documents.
Ross @ CIrcleIT has pointed me to an answer.
It is unclear whether the settings button is or is not supposed to appear in the Editor pane on Wrod on the web but it definitley doessn't
However you CAN get at the settings
Go to the Review tab and select the drop down list next to the Editor button and you can see Editor Settings...
Hope this helps others