During a Teams meeting when sharing your screen, the Presenter mode controls how your webcam is displayed. The default mode is called Content Only, this shows a full screen of content and your webcam appears in a small box 
For presentations where you want to be seen use one of the other presenter modes, Standout, Side-by-side or Reporter.
Select a presenter mode when sharing your screen, or hover your mouse pointer at the top of a screen that is already shared to reveal the hidden tool bar. This allows you to switch modes instantly while presenting.
The larger you appear on screen the smaller your shared screen content appears. Select a presenter mode that best fits your requirement to show the content or your webcam.
