Hi Pablo,
API Composite means Composite API that you may use on web interface as API listener like retrieving information on page load. So this charge will be US$0.014 x 2 every time you refresh the form that has "Screen Initilaized" as launch event for CAPI. So your behaviour has 2 API composite calls.
API Calls (API call to cloud or on-premise) are connector tasks. So if you process or C.API has a connecor like retrieving information from db, then it counted as 1 connector call.
If your behaviour with two CAPIs has 1 connector each, then it will cost 2 connector calls = $ 0.014 x 2.