https://developer.paypal.com/docs/commerce-platform/

It would be nice if there was more information on how to actually sign up to use this?  I followed the steps but the API doesn't let me use it.  I need an account manager?  How do I get one?  Where are the links to actually move forward with using this API?  If this is a limited release product, how can we apply to use it?  Very low effort on whoever created that doc page.