Install the Dashinar plugin and you have a Gutenberg block in your WordPress control panel where you can plan, schedule and setup Webinars inside a Learndash course. All participants in a course are automatically added to the live Webinar. No need for an extra login or software download. This is a plug and play solution.
Setup the limitations for the course in the Learndash settings as Open , Free , Buy now , Recurring or Closed and this will auto add the users login to the Webinar.