Bluetooth-multiple devices paired to single phone. Connection question. Samsung Galaxy S6

Have my first smartphone
Have 3 devices paired to it.
A-Bluetooth headset-one ear for calls, music
B-Car
C-A home wireless phone, handsets that accepts bluetooth. Used for phone calls.

I have it paired in house AND connected with C. Works fine
When I get in my car, it does not automatically connect.

Questions:
1. I walk into garage and have to connect manually to the car. I assume this is normal?


2. Let say I was out of range of device A, would it connect automatically to the car for cell phone use?
Yet to try.


Thanks
Peter