Most popular CRMs (e.g. Infusionsoft, ActiveCampaign, Hubspot, Ontraport, Clickfunnels) and even simpler, single-purposed tools (e.g. bucket.io) have a direct integration with Zoom to register attendees into a webinar.
This is a fairly simple process which requires publishing an app to the Zoom Marketplace.
Because HighLevel currently lacks this feature, registering people into a Zoom webinar requires a more cumbersome integration using Zapier or Make.com.