I need some information

🐧🌻 Erin🍍🦄

So okay I'm really stupid but I need to know how this works.

I'm like super confused about pumping and feeding baby's breastmilk with a bottle and feeding on demand, if you start giving a baby a bottle wouldn't that effect your milk supply when your trying to feed on demand? I get you just pump but isn't the point to giving a bottle to get a break?