Help with aero physics

I'm in the process of trying to become an AC modder, I'm still not able to do many things but i'm making progress. I got a question regarding how the physics of wings in cars work: let's suppose i want to create the physics of a rear wing from scratch, having as a reference only the 3d model of the car. How should i proceed in setting the parameters (position, size, CL, CD, CD_gain, LUT files) to make it as realistic as possible? Are there some formulas that could be of help?