Generally speaking, you will have a Zoom account with users under it—these users’ permissions can vary. To create/start a meeting, you will need a user with Host permissions. For users (students) who will just be joining meetings, they will not need a Host license/permissions. You may find this thread helpful for covering this context in a bit more detail:
If you have further questions about users vs. accounts, support.zoom.us will be your best resource, as this is their specialty, while we are here to answer any API related questions.