I cannot imagine that a presentation is going to be long enough to figure out how to use the camera.
It certainly focuses extremely quickly once you learn how it works.
You can certainly run the entire camera with the right hand. If you want two hands, you can use the left for support as usual, as well as zoom, focus, and if you want, adjusting the control ring (I have it set for aperture in A P and F modes).
My recommendation is to use the touch bar for AF mode, and the right-hand part of the touch screen in relative mode to move focus point. If you haven't tried that mode, long enough to get used to it, you wouldn't know enough to make a decision.