As in English, questions in Arabic are indicated with use of rising intonation.  Here are some question words in Arabic:

مَل (hal) - do (as in “do you?” or “is it?”), used for yes/no questions

ما؟ (maa) - what?

ماذاذ؟ (matha) - what? (used with verbs, such as “what are you doing?”)

مِن؟ (min) - who?

أينَ؟ (ayna) - where?

كَيفَ؟ (kayfa) - how?

متى (meta) - when?

لماذا؟ (limatha) - why?

كم؟ (kam) - How many?

Examples

مِن هُوَ؟ - Who is he?

مِن أينَ أنتَ؟ - Where are you from?

كَيفَ حالك؟ - How are you?

كَيفَ الحال؟ - How are things?

ما هذا؟ - What is that?

مل يوحد؟ - Is there …? or “are there …?”