Starting university (or college) is a big step, especially when a student moves away from home. They will need to adjust to a new lifestyle, new people, new surroundings, new academic requirements and standards. During this time of change and upheaval, you can offer some stability and emotional support.
Try to be there when they need to talk, maybe check-in with them every once in a while. But don’t worry if you don’t hear from them every day – they probably just need some space to find their feet.