How does UNOFF API instagram work?

Question

API

Hello my dears)
, the Instagram Standard API does not have enough functionality.
Please chew and spit, I don't understand how Instagram's private API (unofficial) work. Please be as detailed and intelligible as possible)
HERE I saw this answer

This is not an instagram API, it's an unofficial open API through which instagram applications work.

But it’s not clear to me what it means to pick, and how it happens, what software is used, that is, the full path. And when, let's say I open up, the whole thing, in what language will the requests be? is it possible to change this language for example from php to Go.
I would like to take a ready-made solution on Goland, but I want to understand how they and what they "picked up".
Examples of such APIs :
php
go
python

Answer 1

You take the insta application Decode
and remove the HTTPS protection
Then you set a proxy and look at the requests
The requests will be in the http language and alas, this cannot be changed
There is no other api