Adopting PP?

D • Mama of 2,lost an angel, waiting on number 4💘💓💘 married-blessed💓
My daughter is nearly 7 weeks now and we're actually doing pretty good right now. My (soon to be) hubby, his son and our daughter just moved into a new house in LA but currently I'm at my mom's place in Germany. I commuted between LA and Germany a lot during my pregnancy and helped some refugees here. I've met a little boy who's 3 and just lost both of his parents. I have really taken him to my heart, maybe because of my motherly feelings and hormones, idk but my fianceé and I are planning to adopt him and take him with us to LA. 
Will it even work tho? I've been thinking about it a lot and will talk to our lawyer of course but I moved (back) to America a few years ago and dont really know the laws about adoption, do you know anything about it and am I even allowed to adopt before my daughter is 12 months old? 
We dont have any financial problems or something like that and I will stay at home for like the next 2 years and will go to university after that so I will still be a lot at home... 
Does anyone know about those laws and if refugees (even if they're adopted) are allowed to come and live in America right now? 
I've posted this in another group too because I really want to know...