Please my uncle has forgotten his Apple ID password and the phone number he used when he was registering for Apple ID. Can something be done to get the credentials ?

Please my uncle has forgotten his Apple ID password and the phone number he used when he was registering for Apple ID. Due to traveling from one place to the other. The main reason is, he recently had an accident and he’s been experiencing mental disorder so he can’t recall somethings.Can something be done to get the credentials ?