My baby Quaker JoJo is pretty much weaned now. As for pellets, I give him Zupreem Naturals for medium birds and Tropimix for medium birds. He loves both foods and will let me know when it's time for a refill. However, it's best to keep them on the diet they were already on when they came to you and then you can transition them over to a diet you want them on. I believe there are threads on here that talk about how to do that safely. Covering the cage is a good idea, specially if you're active at night. I cover both my birds at night regardless though. As stated before, DNA sexing is a personal preference. Watch out for those fingers as JoJo started getting pinchy but once I got them a toy and other chewables and spray millet, he stopped chewing on me as much. You're kiddo might not pinch but it's something to watch out for. If they start chewing on you, it's time for a chew toy and mineral block. Introduce toys and other stuff like that one at a time with several days in between to not overwhelm them as they will freak out with each new thing. Give them time to adjust and figure out what the new thing is and to decide if it will eat them or they will eat it.
Oh, once they find their voice, you will wonder if your ears are bleeding. Quakers are quite loud. I can barely hear Sweetie's tweets over JoJo's squawks most of the time when they start their conversations.