I have an older vehicle with early Bluetooth that only accommodates incoming phone calls and outgoing calls to the directory entered in the vehicle Bluetooth system. With my Note 8, I was able to utilize "Readitome" to make other outgoing calls and verbally receive/send texts. Currently the app does not work for Android 13. I have a Roav Bolt hooked up through my vehicle's auxiliary connection which handles calls and texts but only through auxiliary and not through the radio when it is playing.
While the app is not perfect, it is a big help. From what I see I don't think changing some of the specs on the phone will accomplish what I want. But I will be pursuing it further using your suggestions