How to use AirPods as a hearing aid?
You can try using the Live Listen feature on iOS.

With Live Listen, your iPhone, iPad, or iPod touch becomes a remote
microphone that sends sound to your Made for iPhone hearing aid. Live
Listen can help you hear a conversation in a noisy room or hear
someone speaking across the room.

Tap Settings &gt; General &gt; Accessibility &gt; MFi Hearing Devices.
Tap your hearing aid under Devices.
Tap Start Live Listen.
Place the device in front of the person you want to hear.


https://support.apple.com/en-ca/HT203990