Breastfeeding baby

First time mama/ baby is three weeks old and I’ve been breastfeeding exclusively and introduced a bottle to him a week ago because I’ll be leaving Sunday for my birthday. My husband bought a ticket, and if it were up to me I never would have accepted it but he bought them so long ago and I can’t back out now.

I am curious as to how many ounces I should keep in my storage bags?

How many should I leave our for a full days worth including middle of the night?

Also... me and him have been together everyday. Every second. It will be so hard to leave him 🙄 I’m scared he will want to eat and eat for comfort during the time he doesn’t have mama. We have noticed when he is held by others he immediately wants mama

And I comfort him just by holding him.

I defiantly have post partum as well and trying to get the hang of things.

And suggestions and tips will be helpful.

I can only do so much research.