Help with Steering Wheel controls for Xtrons Headunit

[dog2bert]

So my old Xtrons headunit died, but it lasted 8 years, so I thought I would give them another try.
Here is what I got:
Android 15 Touchscreen Radio Stereo CarPlay Bluetooth 5.4 4G 128G for BMW E46 M3

I plugged in the connector that slides, and the radio antenna and it appears to work except for the steering wheel controls.

Any help in getting the steering wheel controls to work would be great.
Also how do you make it so that the lowest volume level isn't so loud.

[dog2bert]

Do I need to plug any of these in?

[Slideways]

There should be a small decoder box for the steering wheel controls.

https://www.dvdgpsnav.com/blog/bmw-e46-m3-navigation-system-support-steering-wheel-control/

[dog2bert]

The head unit can detect the car going into reverse, but still no steering wheel controls. Trying to learn the steering wheels controls doesn't appear to work either.