I used one of these. Can’t beat it for the $ if you want to keep the factory head unit:
Bluetooth Handsfree A2DP USB SD AUX Adapter for Porsche PCM2 PCM2.1 CDR23 911 Boxster Cayman Cayenne
https://www.amazon.com/dp/B07V83PYHJ/ref=cm_sw_r_cp_tai_li2zFbXX50M1Q
What radio do you have? Added one of these to my 2006 with PCM2.1 and Bose and it works great. I did not have the CD changer but this would replace it. You just select it like you would the changer from the main unit. Even gives track info and handsfree. Look for Mr12Volt
https://www.amazon.com/Bluetooth-Handsfree-Adapter-Porsche-Boxster/dp/B07V83PYHJ/