I would assume the 12-18month shoes would fit. Not sure where you’re from but carters also has baby shoes starting at size 2 and they have half sizes! So maybe a size 2.5 or 3 to start with! Also she wouldn’t need shoes inside I would encourage barefoot as much as possible! She’s gotta learn to balance on her own and in shoes is so much harder
Take her to a shoe shop and they’ll measure her 😊