What you (do) now? The correct form of the verb is-

→ At this moment, now ইত্যাদি হচ্ছে  present continuous tense indicator বা নির্দেশক। 
→ অর্থাৎ বাক্যে At this moment, now নির্দেশক শব্দগুলো থাকলে বাক্যটি সাধারণত present continuous tense এ হয় ।

Present Continuous Tense টির WH question যুক্ত Interrogative Sentence এর গঠন : 
wh question + am/is/are + sub + verb + ing + extension + question mark (?).

Correct Expression: What are you doing now?

Example Sentence:
1. Where are you going at this moment?
2. I am writing this response to you now.

Source: A Passage To The English Language: S. M. Zakir Hussain.