Help Me Understand Pumping

FTM and my baby is 1 week old. Breastfeeding was pretty tricky at the beginning but now that my milk is fully in and baby is getting better at latching, it’s going pretty well. I was told by my pediatrician that I can pump sometimes so that my husband can feed baby a bottle to help. But I’m so confused about how this works.

If my husband feeds baby, I still have to express at that time anyway so what is the point?

I got some pumped milk storage a couple of days in a row due to baby being extra sleepy in the middle of the day and missing a feed. However, in the last couple of days, he has woken up more and hasn’t missed a feed. This morning I decided to give him pumped milk that was stored because he was hungry again about an hour after he breast fed. But he ended up wanting more so then I also breast fed. So now I don’t have any stored pumped milk and I don’t know when I would pump again vs breastfeeding?

I know that eventually I’ll want some pumped milk stored so that I can be away from baby. But how do I start building up that storage?

TIA for any tips/advice!