I suspect you have found a phone. In which case whether it was lost or stolen is not relevant. Turn it in to your local police. If it is activation locked you can never use it anyway so be the good guy. 😀
Other than turning it in to the police, you cannot. Apple does not take reports of lost or stolen devices. And there are no international, national, regional nor local databases or records of stolen or lost consumer electronics. Nobody collects and provides that information, anywhere.