How can I model a building in Unity using lat, long, alt coordinates?

Hi,

I'm working on a project where I'm supposed to create a model in Unity of a real world building by getting latitude, longitude and altitude coordinates from a JSON-file. Each coordinate point is supposed to represent a "corner" of the buildnings floor shape. I've gotten as far as deserializing the JSON-file, and storing the coordinates in a List. But now I'm not sure how to actually transform these LLA-coordinates into Unity XYZ-units. I want to be able to import diffirent JSON "Building shape"-files into Unity, and have Unity create the floors of the building. Also, later on I'd like Unity to generate walls based on these floor shapes.

I've done a bit of research and it seems that the real world coordinates that are based on earths spherical shape cannot simply be transformed into X, Y and Z in Unity. I've seen a few posts of something similar to this which includes a bit of math, which is not my strongest skill.

I'm new to programming and this project is part of an internship I'm having through my education. I don't really know where to go from here. What is the best way of doing this?