that is very normal that small children after taking breastfeeding will regurgitate small amount of milk. if the amount of milk is less than 10 ml no need to worry. this curd like milk is normal and no treatment is required. but if the quantity of milk is more than you have to rule out any gastric problem the child might be having (can give drops domstal 3 drops then wait for half hr and then give milk) you can decrease the the regurgitation by giving more burping time to the child. also due to common pathway at the back between nasal cavity and the oral cavity the milk can come out through the nasal cavity also during the regurgitation and vomiting which is normal meet your dr if vomiting is in large quantity and happening again and again

Do proper burping