Don't let the speaker at the other site continue if you can't see or hear the presentation. Interrupting the speaker for this purpose is not rude, but helpful. Speak to camera for remote site. The camera is usually placed on top of the monitor where you see the other site. If you look in the direction of that monitor, the camera will pick up your image well.
Some cameras have an automatic tracking feature.
That means when you speak, the camera will zoom in on you automatically. Wait for reactions. There is a short delay from the time you speak until the other side reacts to your comment and responds. This is usually about 1 to 1.5 seconds. You should enjoy your ITV class experience.