What milk is it? If its breastmilk it dependa on what you eat. Or maybe you didnt take propee meals. If its formula milk, maybe you shake the bottle. There is ways to prevent colicky in babies. Please google on how to prepare formula milks to babies.
It’s completely normal for babies to spit out during burping. It’s a sign of good breathing and healthy baby.
It indicates that they are healthy. They splits only extra milk
That's completely normal. They spit extra milk.