You can choose from hundreds of templates. You can use them as they are or customize them to suit your needs.
To make an HTTP request using values from another module, use the JSON generator to define the data structure and modify it as per the convention of the service the request is sent to.
From an Array of Collections (Names, Emails, IDs), you can extract an item (Email) and/or extract the value of an item (a specific email) using functions.
Every time a Bubble workflow runs and triggers an API Call used as an action, Integromat will receive data as a JSON and parse it to be used in subsequent modules.