Thank you for your answer. However I am still confused about question 1 and 3.
1. I have already paid SEVIS I-901 fees when I applied for my visa. I got I-20s for my dependents as well. Do I need to pay SEVIS again or the previously paid SEVIS receipt would work?
3. Regarding DS-160, the application ask for two SEVIS IDs. As mentioned below.
SEVIS ID of principal applicant:
So in this case, I should enter following data. correct?
SEVIS ID: <Spouse SEVIS ID>
SEVIS ID of principal applicant: <My SEVIS ID>