I’ve found some AirPods how do I find the owner

You cannot find the owner electronically.

Turn them over to the authorities.

If the owner has turned on Lost Mode, holding the Airpods near an iPhone will reveal a message about the owner.

myaka's response is correct - if (and only if) the owner chose to set up the AirPods this way. Many owners do not set up messages to display even when AirPods are in Lost Mode.