Hey @viglob,
Depending on your use case, you can authenticate via OAuth, or JWT.
To Create a Webinar, use this endpoint:
https://marketplace.zoom.us/docs/api-reference/zoom-api/webinars/webinarcreate
To subscribe people, use this endpoint:
https://marketplace.zoom.us/docs/api-reference/zoom-api/webinars/webinarregistrantcreate
Let me know if that helps! 
Thanks,
Tommy