Indeed. Consider -
तू जा रही थी - you were going
क्या तू जा रही थी - were you going? (putting क्या at the start turns a statement into a question).
तू कहाँ जा रही थी - where were you going? (we have used the word कहाँ - where).
wh words in English make question in English... what, where, when, etc similarly hindi has words when used in the starting of a sentence makes it a question. क्या what क्यों why कैसे how कब when कहाँ where कितना how much// how many and there conjugation with masculin, feminine and neutral too...