Baby carrier you can carry things in?

Any help or recommendations of back baby carriers with enough room for a bottle, few snacks, wet wipes and 2 nappies will be hugely appreciated! I’m yet to find one 😅 I don’t drive and dislike my very active boy being limited to a pram on fun days out (and then pushing the empty pram!). I can’t get my toddler sling and backpack to cooperate as the back pack just slips off my shoulders 🙃 please help! …maybe a combo or a cross body fanny pack with some sort of carrier?