Yes. Only the host has the access to Livestream the meeting to Youtube. The prerequisites are the Youtube Live stream Key to be available and no live streaming restriction in the past 90 days.
1. Once the meeting is started, click on Toolbar icon at the bottom right end of the meeting room
2. Select the Youtube tab in the toolbar
3. Click on "Start Live Stream" link in the tab
4. Enter the Youtube live stream key and click on Live stream.