Traduko - Turka-Čina simpligita - adın nedir yas kaç nerelisin

What is your "name" = 请问贵"姓"?
Also, you gave two translations to the second sentence. You might want to choose one of them and post the other as a note. Thanks.

Thanks for your comment.
I suppose that when we ask someone's name , it should be ether first name or last, and when we address to a stranger someone unknown, maybe the better way is to ask their last name=”姓氏“.

And for your second question, when we speak to someone young, to a child, we can ask "几岁了，多大了“， and when to use a more "genteel" tournure, maybe the other term is a choice.

Thanks again

When you are asked what your name is you don't say Mr. Something do you? You tell them your full name, and the one who asks will be the one who calls you Mr. Something. So I guess it's not a first-name-last-name thing. Plus, Chinese see both names as a whole.

As for the second question, that's what you should be putting into the note.

Thank you for your remarks, you are right!