Using API's

Hey everyone, Right now I'm currently trying use a few API's with a streaming program called Lumia Stream. I'm still fairly new to working with API's, and have a few questions. Right now I'm trying to use the newly released Threads(.net) API, as well as the Instagram API for some potential automations. One way API's can be used in their program is via a Manage API section. Which gives the option to GET, PUT, POST, PATCH, DELETE, and DELAY. While I'll obviously mostly need GET or POST. I'm a little confused on how to utilize their program to properly use an API. For example with the Threads API, I need to GET the ID and Name of my account. Then I need to use POST with the variables to create a media container. Then use POST again to create the actual Threads post with the Container ID... How do I set it up so when creating the media container, it use the variables from the GET. Then when the post is ready to publish, the last POST uses the variables from The GET, and previous POST call? I haven't really been able to get answers from their Discord. So I'm confused If I'm misunderstanding something or if I'm just missing something. There's also an option to use JavaScript, but I feel like I should be able to use this in the same way...