This is exactly what i am doing with my car for two years now. My cars stereo doesn’t have a Bluetooth but has a 3.5mm headphone jack. So i use the lightning to 3.5mm female dongle that you can buy from any apple shop or even find within some new iphone boxes and a male to male 3.5mm jack cable and I connect my phone to my car stereo through the lightning dongle. Two years now i am happy and it works perfect for everything including youtube , music , calls , everything.