How to work with Web API?

Question

API

Sorry for the stupid question, but I don't understand much about this.
There is documentation on using the web api which states:
"First of all, in order to be able to use the API methods,
you need to make a POST or GET request for authentication to the address:
site/login.php. "
Then I understood, just in the address bar I write ?login=login&password=pass. Authorization is successful.
But I don’t understand how to work further and pass other parameters.
Maybe there is some literature or other resources on this topic.

Answer 1

Depending on whose API you are using. Each API comes with documentation describing requests and parameters for operation. Examples
vk.com/dev/api_requests
https://dev.twitter.com/overview/documentation
etc...