Sampling Microphone / headset for A2DP or HFP through ESP32

First forgive me if I posted this in the wrong forum. I’m designing an adapter board that will utilize A2DP and or HFP and sync to phone. The ESP32 (Thing Plus) will sample the microphone and stream the call to an amplifier / speakers.

I’ve got A2DP working and powering speakers using I2S Audio Breakout https://www.sparkfun.com/products/14809. However, I’m not sure what I need to read the microphone. I have seen these boards but they have the microphone built in https://www.sparkfun.com/products/18011

Can I use a simple OpAmp like this for the microphone? https://www.sparkfun.com/products/9816