Baby is eating so much. Can we do anything?

LO is 3 weeks old and is eating 4oz every 2-3 hours day and night, and sometimes thinks she wants more. I’m all for feeding her whatever she wants and never deny her (which I think is the right move, right?). Sleeping is hard, she is still up every 2 to 3 hours wanting her 4 ounces. Is this normal? Is there anybody else who has experienced this? Are there any tips or tricks we can do? Thanks!