There are several international companies where you can speak english and have no problem whatsoever, there are also a few international schools and kindergartens, However, in order to communicate on the streets it is important to be able to speak at least some german. It is also important in normal logistics such as going to the bank, buying a bus ticket. In the larger cities as well as in very touristic places most people speak english (Most young people do as well). Once you leave those urban areas, evn for midsized, more rural towns, that ability almost disappears. The older generation also have a much lower ability to speak english. English knowledge is definately linked with education her, anyone who went to gymnasium, and or university should know quite a bit, so communicating with you doctor, lawyer, dentist, etc... shouldnt be any issue, the level drops in the demographic who work in more blue collar jobs, so without german knowledge you may find yourself in difficulties with the postman, bus driver, sales clerk, hair dresser, waitress (not applicable in high tourism areas), etc...
There is also a strong desire in the austrian population to see people 'integrated' which can go to the point of wishing them to become more austrian than an austrian (this is again especially true in more rural areas), Dont overlook the fact that although austrians are quite nice people and friendly they are also not very open to foreigners or alternative lifestyles, the extreme right party does suprisingly (alarmingly) well in every election. Some of this tendency can be softened a bit by speaking german (at least making an effort).
Most universities offer an entry level german course for a reasonable price. I would recommend taking at least one year (A1 and A2) in order to communicate), a second if you would like to sound a bit more professional at you job (B1 and B2), and you will need a third (C1 and C2) in order to enroll at university. You can just take a placement test if you know some german already or are studying online, although I do recommend attending a course as it will provide contact to others in the same situation. Again although austrians really are friendly and polite (most of the time), this is a very family oriented culture and at holidays, many weekends, etc... many will spend the time with their families making it all the more important that if you dont have family here you know others who are also available.
There are of course language schools such as berlitz and a number of others but their fees vary. Berlitz, for example probably costs areound 800 euros for a course whereas couses at D.I.G. are between 160 and 400. Urania is about 130, University courses are closer to 100 if I remember correctly,
https://www.berlitz.at/Gruppenunterrich … L_00010685http://www.dig.co.at/de/http://www.urania.at/unser-angebot/sprachkurse.htmlhttps://sprachportal.integrationsfonds. … XcQAvD_BwEhttp://zsbk.unileoben.ac.at/de/4516/https://treffpunktsprachen.uni-graz.at/ … nsivkurse/