Select Present from the menu above the canvas to start the SCREEN FOLLOW MODE. In this mode all active collaborators or anyone viewing your project using the public link will automatically start following your canvas and will be able to see what you see on your canvas.
Press Stop in the menu above or in the presentation mode menu at the bottom of the screen to stop SCREEN FOLLOW MODE.
To stop following someone's canvas when they are presenting, select Stop at the bottom of the screen.
To follow the presenter again, select Follow. Or select Present to take over the presentation and present back to the original presenter/collaborators.