Perching And Feeding Question Please

Hey There!

I have a baby Cockatiel named Lulu. She is 51 days old today. I was wondering around what age do they come off the bottom of the cage and start sleeping, eating, playing and perching like an older bird does. Sometimes I'll find her perched but 99% of the time she's at the bottom. I put everything down there for her. She has food, water, treats, and toys at the bottom aswell as the top. I gradually weaned her off of the morning and afternoon formula feedings but she still gets a night feeding right before bedtime. Do you know when I should stop this?