Each API endpoint in the reference doc lists the account type required for users to use the Zoom API. We will be releasing our new rate limiter in the upcoming days where APIs are rate limited by account type. You can learn more about the upcoming rate limits here: https://marketplace.zoom.us/docs/guides/announcements
We recommend that users have at least a Pro account to consume Zoom APIs in a reliable manner. The API access is directly related to the type of feature. For example, Dashboard APIs are only available for accounts that are on Business or higher plans.