Rebilly's API has over 300 operations. That's more than you'll need to implement your use cases. If you have a use case you would like to implement, please consult us for feedback on the best API operations for the task.
Our getting started guide will demonstrate a basic order form use case. It will allow us to highlight core resources in Rebilly that will be helpful for many other use cases too.
Within 25 minutes, you'll have sent API requests (via our console) to create a subscription order.