When you connect your big screen (a projector or a big TV screen) to your laptop, use the “Extend display” option instead of “duplicating” the display or using the TV as your only display.
Next, you want to use the “Broadcast” view for polls and questions. The attendee view of the Pulse is better than the presenter view (and there is not a broadcast view.) You want to have each of those pages in their own tab on a separate window that’s visible only on the large screen. If the name of your meeting is MEETING_NAME, these are the URLs you would open in a new window on your big screen (note that #pulse does not have a slash preceding it but #questions and #polls does):