Problem with the pickup creation process

I have a proplem. I don't know what API to call next after creating a shipment. After creating a "https://developers.easyship.com/reference/shipments_create" shipment, what APIs do I need to call afterwards to get data for parts like Manage Shipments or Pickups. I feel quite sad that there is no dashboard to test data on sandbox environment, currently I don't know what steps the process will include, what APIs to call to get data from shipment to pickup. Currently, I have not updated my account to Premium and am still in trial mode.

Thank all!