Bringing in baby clothes, toys, bottles and car seats can be a strange change for your dog. They will be naturally curious of a new item in the house, if not a little fearful of the scary pram monster.
Allow your dog to sniff around new items, you can reward them for doing so. Do not allow them to play with any items or chew on them, and if they do perform a positive swap, not drawing too much attention and definitely not shouting at them or telling them off.
When you get your pram set it up in an area that where the dog can see it, but does not have to walk past it or interact with it. You can drop treats around the pram so that the dog can investigate at their own pace. Once the dog has had a few weeks to aclimatise to the pram entering the home you can move it into a more prominent area - such as the living room where they will need to walk past it on a day to day basis. Again, you can drop treats around it so the dog can investigate it.
Once your dog is used to the pram being stationary they will then need to learn that the pram moves -and that's scary... Begin pushing it back and forth in slow motions, treating the dog. Do not force them to come close, toss treats over to your dog if they are at the other corner of the room. Continue until the dog loses interest.
Next step is to move the pram around the home, start off short and build it up to 5 minute sessions. Treat the dog for calm behaviour. Allow them to remove themselves from the room if they are not happy, there is no point chasing them around with the pram as they will only learn that it comes after them.
Introduce the pram on a walk - begin very short walks, if someone can walk the dog beside you whilst you push the pram that would be best. Gradually decrease the distance between the pram and the dog until you are holding the lead with your dog walking beside the pram.
Be patient. Your dog has never experienced this before and they will need lots of time to feel safe around new objects.