Have you tried yet? Some babies transition very very easily. Others don't. Until you actually try for a few nights you won't have any idea if you'll need to do any kind of transition or not. There are hundreds of transition tricks (from sleeping with the crib sheet for a night or two so it smells like you, to moving them once they're already asleep, to staying with them... literally hundreds of things to try).
It's fairly normal for babies to still be waking to eat every few hours, especially when they're in a growth spurt. There's no way to "get" a baby to sleep through the night if they're not ready. It's just a choice of to ignore them or see to their needs.
As has been mentioned, babies often will not sleep through the night when they cosleep. Some do, most don't. We all move around a great deal when we're sleeping so for a light sleeper, every movement during the wrong cycle in their sleep will wake them. Making sure their bellies are as full as possible, and that they are dry (even changing them while the sleep) helps. But many baby tummies just aren't big enough for 5+ hours of sleep. Most are at around 6-9mo, but many aren't. Some 2 week olds have bellies big enough. It really is on a child by child basis. Another thing is to make sure that they aren't overtired when you put them down (any baby that's overtired that I have ever known will wake and wake and wake).