Mercedes C-Class w203 2001 Aux Input - Creating DIY Aux Input for Radio with Disc Changer

Hello. I am looking for a way to make an aux input in my car. Mercedes C class w203 2001 The radio has a disc input and once had a changer (unfortunately I'm sorry I don't know what model it is because all the stickers have become illegible). As far as possible, if someone knows what and how it could share the experience and say what solution would be the best.
I apologize in advance for all errors. If I did not find the right topic, I will move the info to the right place. Thank you in advance for your help.

It would be appropriate to give a photo of the sockets and a radio model

I am sorry for not responding so long.
So:
Type: Audio 10
Model: BE 6021
Series No. : 21473424
Pin arrangement in the attachment.

You can leave the device inside the device. You won't give the signal to this connector.

If you have skills and a scheme, it is feasible, but whether it is profitable is your decision.

Are there any radios that have an aux or USB input and allow steering from the steering wheel for some reasonable money?
Because the soldered cable works on average (tested in avensis). Some opinions from someone who used this solution.

Tomaszkubiak11 wrote:

And there are some radios that have an aux or USB input

For this car - no. This control is a let it go.