switching from formula to breast milk

Hey guys, me again lol I hate to keep asking questions about breast feeding but quiet frankly... I'm clueless. for the past 2 weeks I've been pumping and dumping my milk to keep a supply so that when I finish my medication I can start breast feeding my daughter who is now 16 days old. today I finish all my medicine, and sat I can start feeding her the milk when it's had time to get out of my system completely but in confused on how all this works. my daughter is around 8lbs, and currently drinks 2 oz of formula every 2.5-3 hours something every 4 hours during the night. is this the same amount of oz she should drink in breast milk as well when I get to start? or will the oz be different, and will the time between feedings be different? i will be exclusively pumping, she will not be latching ... not to sound dumb, but I don't even n is where to begin but I really want this to work 😣 will this transitition make her tummy hurt?