With the newest version of the boxlight software students can "Cast" to your TV. You will need to turn on WebCast and know your code but it is easy to do. Then your students go to a website (https://w.unplugd.app/) and put in your code. You can turn WebCast on and off easily enough. The code or ID is blacked out in the image below. I would NOT show students this screen - it is too small and you should not make your IP address public. Go old school and write the code and website on the board! Or better yet - make a page and save it to files folder on Boxlight.
Students will be give then option to present whole desktop or tab... It really should not matter. They can also check the box to play audio. All up to what you are wanting from students. So have at it!