I am a law student and 20 years old. I speak English and German fluently, as my mother is from the United States and I spent a significant part of my life living in Vienna. I also speak French, Polish, Russian and Italian (each at a B2 level), so I can explain complex grammar structures of the language I'm teaching in my student's mother tongue, provided they are from the countries I listed. I have taught both younger and older people in the past, usually foreigners who moved to Vienna. I am a patient person and being an avid language learner myself, I can easily relate to the difficulties newbies might experience when being confronted with a new language.
I recommend registering for a "Sprachkurs" at the "Sprachzentrum Wien Altes AKH". This is, of course, not mandatory, as languages are learned best by simply spending time in the country the language belongs to. Reading and watching movies and also contribute to a better understanding of the language.
If starting from zero, I would say that it would take 1 year to be able to hold one's ground in day-to-day conversations, and it might take 3-5 to reach a level one could consider fluent. This naturally depends on the learner.
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