Help please!

Jordan • Married 💍 boy mom 💙 second boy due oct 2020 🥰

I made the last minute decision to breast feed while in the hospital and he latched the whole time we were there and stopped when we got home. So we’ve been hauling formula and I just today got my pump. He’s a week old today. I just pumped for the first time about 15 minutes on each side and only got a little under an ounce and I know it’s probably because my body was starting to dry up. But my question is how exactly do I give him this ounce? He’s eating about an ounce and a half every two hours so I wasn’t sure when and how to give him this ounce.