How to export swagger sdk API to yii2 advanced project?

Question

Yii

In the open I tried to find a clear guide for complete beginners about creating an API using swagger codegen.

The main issue is that after exporting the SDK, I get an archive in which the readme.md file does not really help to figure out what and where.
I would like to get more advanced instructions on how to use the generated API in the yii2 advanced project in the end.

I will be glad to any links with information or a detailed description.