I am Brazilian and my girlfriend is German. Some weeks ago she had to go back and we thought about the possibility of me going to Germany so we could live together. For that, our initial plan was me to visit Germany with a tourist visa (Brazilians are not required for visits under 90 days), staying for a period like a month or so to see if I would enjoy the place, and if I do, apply for a temporary residency visa while I still am in Germany.
Is it possible to apply for such visa within German Borders? Would this kind of relationship be acceptable for requiring a visa or we would need to be married in order to require such thing? How about work, am I eligible to obtain an work and living visa since my main goal is to stay with her and for that need to get a work in order to sustain our household?
I have been looking for answers all over the internet, but there's little to no information in Portuguese and when I look for something in English, I normally find information about US citizens that can live in Germany under certain specific conditions, which is far from this scenario.