Unless you're involved in a crime or being suspected of a crime and are being arrested then you do not have to tell the police your name or identify yourself in any way to the police.
If the police request your name and ID and you haven't been suspected of a crime they still may threaten to arrest you which they cannot do so always ask for them to get their supervisor to speak to you.
The police officer does need to identify themselves though but you do not need to identify yourself.
Now if you're driving a vehicle and are stopped you do have to produce your drivers license to the police officer who pulled you over so in that case you have to identify yourself but anything else you do not have to identify yourself to the police.