I think many software like messenger, QQ, Skype, allow you to make video phone call, both side needs a web camera, which is either embedded in your laptop or connected to the PC.
Thank you very much for your reply. I just downloded SKYPE but my sister said they use 腾讯QQ, we are not sure if SKYPE and 腾讯QQ can make vedio phone call each other. Also it seems I can not download 腾讯QQ .