Ounces of breastmilk

Hi guys, I’m not sure if this question is silly. But I’ve EBF since my baby was born. She’s 3 months old, 9 lbs 6oz. She was born at 38 weeks (full term) but at 4lbs. She’s doing really well with eating and weight. My husband is going to give her bottles two days a week while at school and I’m not sure how many oz to give her? I know she’s 3 months but she’s still so tiny (9lbs)

Should I contact pediatrician and ask? Or just kind of feel it out and see what she takes!

Anyone else in the same situation as me?