Bluetooth issues on iPhone

[ou2mame1]

I'm having an issue with my iphone. If I'm on a call with my bluetooth headset and turn my car on, my call gets automatically routed to my car stereo. Also when I pause music on my stereo and connect my headset later, music will auto play sometimes. On my android phone, I can disable calls on my stereo and media on my headset. How do find these settings on the iPhone? I've included some pictures of my bluetooth devices on my android phone to show the options I can't find on the iPhone.

Basically what I'm trying to accomplish is... I don't ever want music on my headset, and I don't ever want calls to go through my car stereo.

 

[bobsgolf]

You can't dictate ,Calls only ,or music only ,to a specific source ,as far as I am aware