API REQUESTS CREDITED ARE DAILY, MONTHLY OR YEARLY?

On free plan, API requests are credited only once when you create your account and are limited to 10,000 requests only. On premium plan, there is no limit to API requests, you can call APIs as many times as you want.

Is there any limit on APIs I can create, update or delete?

We are not monitoring and limiting users to Create, Update, Read or Delete. It's a simple model, you purchase the premium plan and you are free to utilize platform's capability without bounds.

What service do you use for the billing

We are using LemonSqueezy for transactions and management

Where can I check the number of Requests utilized

You can check the usage on your billing dashboard