Language Portal is a fee online resource also offering free live lectures
https://sprachportal.at/en/mein-sprachportal-at-a-glance
VHS is a provider for general education in Austria and offers semester courses
https://www.vhs.at/de/k/sprachen/deutschkurse-daz
Sprachzentum of Universität Wien is a provider for courses in different formats
https://sprachenzentrum.univie.ac.at/de/deutschkurse-1