How do I answer the question
How do I answer the question, ¿Qué estás haciendo en este momento?
2 Answers
You tell he/she who is asking you the question exactly what you are doing at that moment.
You're being asked:
What are you doing at the moment?
estás means you are or are you
so you'll need to answer using 'estoy' / I am .....
plus whatever you're actually doing
Estoy cenando. I'm eating dinner.
Estoy leyendo. I'm reading.
Te estoy hablando. I'm talking to you. (a tricky one as the 'to you' needs to go in front of the 'estoy')
Hope that gives you some ideas - all the best!