My baby is 6 months old

I overheard a family at daycare with a younger child and their kiddo eats 6oz+

Mine only eats 3-4oz of breastmilk at a time. Still about every 2-3 hours. She does get 2 servings of oatmeal.

She sleeps at night. Wakes up 1-2x to eat and crashes.

Am I doing something wrong? Shes tall and skinny for her age but the dr said its following a normal trajectory on her growth chart.

She loves her oatmeal but not much else.

Normal? Advice please?