ESRI Academy provides online courses. Some are paid but you can also find free courses and courses that require an ESRI maintenance subscription. The latter is covered by the AU Campus license agreement, facilitated by the GIS committee.
As student or employee at Aarhus University, you will be able to follow a lot of ESRI GIS courses at your own pace, both at beginner and advanced levels as well as on highly specialized topics.
At first you need an ESRI user account, and it has to be associated with Aarhus University. Please contact you local GIS committee representative or write to the GIS committee ( gisudvalg@au.dk ). They will send you an inivite and instructions to join either with a new or existing ESRI user account.
Enjoy your GIS studies.