Hi Beep:
>First, my father lives in another country and obviously I can not take his original passport with me to the interview. What can be done?
You are expected to take original documents with you.
Ideas:
You could ask the USCIS through the application form, as there is messaging there
You could ask your father to FedEx his passport to you
It may depend on what other original evidence that you have, but it would be better to ask USCIS directly.
>Second: after the interview a few people have mentioned they got the US passport in the US. Are we supposed to travel back on the new US >passport if we get it , or can the child travel on the passport on which he entered? Because the return tickets will be on first passport.
My understanding, and I am not a lawyer, is that the child had to enter AND leave on the original non-US passport. And as a US citizen is required by law to use their US passport if they have one, I chose to not get the US passports while in the US.
Instead, we returned to our home country and have applied through our local consulate, and the passports are on their way.
Also, this whole process is a LOT, so adding on the application for passport and waiting for that to arrive in time before leaving the USA, it just made more sense to me to do it later, so I was not too stressed.