My child/kloc-will go to Austria to study in October. Can I stay with him? thank you

Generally speaking, it is unlikely. Need visa synchronization, school invitation (that is, invitation letter) and a lot of trouble! Especially the visa officer can't understand accompanying reading! The usual practice is that after studying abroad for a year (or a period of time), the child will send an invitation letter to his parents (immediate family members) in China through the signature of the international (international) student office of the school, and then accompany him to apply for a tourist visa. Generally, the time will not exceed 6 months (basically one semester).