Oh she's adorable! She looks about 2 weeks old. Chickens start to loose their little fluffy feathers and get adolescent ones after about 2 weeks.
Newly hatched chicks are more or less self sufficient. They just need warmth, chick feed, and water. You're going to want to get her a store-bought feeder and waterer as well as store-bought chick feed. Chickens have a tendency to knock over/poop into everything that isn't specially designed for them. Chicks also might like seeds, but they're not the most nutritious thing to feed newborns and feeding them too much "junk food" can create poor feeding habits as adults.
If you haven't already, you're going to want to start a brooder box and get some wood shavings (not cedar) or sand. A dog crate or large plastic tub work great. She's going to need a heat lamp as well. You're going to want to get her up to 85-90 degrees! and then reduce it 5 degrees per week until about 70 degrees. If she's sleeping a lot or huddled around the warmest spot, it's likely because she's too cold. Although it is perfectly normal for a chick to sleep a lot, she should walk around and eat on her own.
I'd also second the recommendation on getting her a friend. Chickens are social creatures and don't particularly like being by themselves.
As always, and good luck on your new chicken adventure!