Hello there! I am Charity. I'm glad to help you today!
Thank you for the information. You will need a separate microphone to use High quality audio/stereo and microphone at the same time. This happens because of how Windows handles Bluetooth audio profiles with the AirPods Max (and most Bluetooth headsets).
Stereo (A2DP): great audio, no mic
Hands-Free (HFP): mic works, but audio quality drops
Also, The official Apple Lightning to 3.5mm audio cable only transmits audio output, not mic input.
Kind Regards,
Charity
Please note that things might need more than one reply to completely resolve your issue, as it will completely depend on the complexity of the question and the amount of detail that you have provided me.