How minimap are created in the games like GTA?

Hey, I have created a complete model with different rooms and floors. Now I want to create a mini map for this architecture model. It just that I don't know how these maps are created. I have tried to create by myself based on my assumption knowledge but it is not good. Below are link for which can give you guys general idea:
Below is the original map model which is render from top view:
https://ibb.co/4K7b2hf
Below is the map which I have tried to create by placing icons on the map:
https://ibb.co/vwyhRy7