When to pump?

I’m going to be breastfeeding for the first time. I can get a breast pump through insurance so I went ahead and have a Spectra ordered. I am a SAHM and no one will be babysitting & dad works a ton then sleeps so I’m going to be feeding baby every time🤷🏻‍♀️ I want to just breastfeed baby but I would also like to have a milk stash saved in case I ever did want to let someone feed the baby or have an emergency and have to let the baby be babysat etc. so when do I pump? I’m confused on that, like if I pump will there not be any milk for when baby is ready to eat?? I have no one to ask & don’t know anyone that has breastfed so please don’t be rude. Simply trying to educate myself.