it seems impossible to find a cable that will pass audio through so best try a Bluetooth adapter such as the Bovee 1000. Can find on Amazon. This connects to a 30 pin connector. There are other similar products.
But my 30 pin connector did not pass power through to the Bovee so I also got a “Xtenzi Charging Converter 30 Pin Pass Through Adapter XT12V5 Compatible with iPod iPhone iPad Car Vehicle” but that didn’t pass power either.
so I then got a “AINOPE USB C Car Charger for iPhone 15, 67.5 W Car Charger” and a USB A to micro B cable …… plugged that into the cigarette lighter socket and connected the micro B end in to the Xtenzi adapter and it worked …… a blue light will flash on the Bovee 1000 to show that you can connect your phone by Bluetooth.
I could then play music and move through tracks using the car’s audio controls (probably there’s an “iPod” option on your car stereo)
everything I mention is on Amazon