One customers multi teachers

Good morning,
A client of mine would like to develop a website for his business.

As solution provider I want to to be able to schedule video conferencing meetings on behalf of his customers, using an API (or anything that does not need human intervention) for programatic creation and deletion of rooms so that they can start and attend video lessons that potentially could run at the same time.

I estimate to have max 20 participants for each meeting.

What is the best solution? I buy one account or many?