Information to apply the master’s programme as student can be found in the link below:
It also has an overview about all necessary documents and steps for the admission at the TU Wien. Those you have to deliver to the admission office and then they start with an equivalence assessment. This decides on an admissible application for a master’s programme and as part of this, you can be prescribed with courses of up to 30 ECTS. The admission can require up to 12 weeks processing time and the documents have to be send per mail (not per e-mail!).