Is it possible to get the Bluetooth history for an iPhone 14 Plus?

I'm not sure I understand your question? All you can see is what devices are currently paired with an iPhone, by opening Settings > Bluetooth. If a device is paired with the phone you can see it. If the device has been removed from the phone, there would be no way to see that it might have been at some point.

What exactly are you searching for in Bluetooth History? Under Bluetooth in the Settings app, you should be able to see all of the items that are setup to connect with your iPhone. What it doesn’t show is the time stamp of when those items were connected previously.

Axel F.