The general characteristic of English questions is the use of an auxiliary verb in the inversion at the beginning of the sentence. Let's see how this auxiliary works depending on the type of question you're using:
They need this kind of answer so they are also called "total" questions. The structures is AUXILIARY+SUBJECT+VERB.
Is he in our class? → Yes, he is.
Do they speak German? → No, they don't
Did you study English here last school year? → Yes, I did
Can you understand me? → Yes, we can.
Are you coming home early today? → Yes, I am.
These are also called wh-questions, when you only ask something in particular, that is, a "part" of the sentence; these questions start with WH-words but you also have the inversion.
WHERE was he born → He was born in Murcia.
HOW MANY children have you got? → I've got 2, a boy and a girl.
HOW MUCH sugar do you need? → Just a little.em>
WHY did you phone her yesterday? → Because I wanted to meet her.
Exception: when the WH-word has the function of the subject you don't have to use the inversion.
WHO is coming tonight? → A few friends (THEY are coming)
HOW MANY friends are coming? → Just 3 or 4 close friends.
WHAT happened to you? → Nothing (nothing happened to me).