i have 2 web apps.one system should feed data to the other system using an api which has been integrated.i have not learned alot on apis but i have researched and have a clue on how they work.this is how i have understood the api is registered in the api.php i have followed the the url on the api.php and ran a post method on postman but it doesnt show anything.which is the process of reading how an api works,