Outings with baby and bottles

Lauren

So tomorrow I have to take my baby boy out for most of the day...it will be our first all day outing. Have errands to run and family to pick up from airport. I am currently breastfeeding and bottle feeding. Breastfeeding is extremely painful for me so I’m trying to give it some time and just bottle feed right now. But I have no idea how to keep the bottles of my Breast milk good all day. I have a diaper bag w freezer pouch and cold pack will that keep the milk good for most of the day? And what do you do to heat it when baby’s ready to eat? May be silly questions but FTM and struggling. 🙁