Reported questions are not complicated.

So now you have no problem with making reported speech from positive and negative sentences. But how about questions?

In fact, it's not so different from reported statements. The tense changes are the same, and we keep the question word. The very important thing though is that, once we tell the question to someone else, it isn't a question any more. So we need to change the grammar to a normal positive sentence.

Wait what?

Confusing? Sorry, maybe this example will help:
Try to complete this practice when you finish reading the examples.

http://www.englisch-hilfen.de/en/exercises/reported_speech/questions.htm

Direct Question	Reported Question
“Where is the Post Office, please?”	She asked me where the Post Office was.
“What are you doing?”	She asked me what I was doing.
“Who was that fantastic man?”	She asked me who that fantastic man had been.