@rokiroki Let me be the first to say Welcome! BAS is a fantastic piece of code!
For your login, you'll use the Browser commands to navigate to the url(s) and complete the steps like that of how you would as a person, click X button, type text in login/password box, etc.
For your Bot <--> Server communicate, you'll want to use HTTP Client Get/Post request, get content and Json.prase the return (if its JSON).
If you'll wanting the URLs to be launched as multithread, add the URLs as a Global Variable or create a resource and use them that way with a _call_section()!
(I'm current replying from my phone so the code is just non-working examples)
Check out the wiki and learn by each example if you haven't! I'm always here for the English community so drop me a PM when ever you get stuck with something!