First of all, you need to check the conditions that Germany applies for Bulgarian migrants. As far as I know, the labour market restrictions for Bulgarians and Romanians are still in place in Germany. Which means you either have to apply for a work permit (again, you need to check for the conditions) or work as a free lancer (pay your own taxes and so). The last one is kind of tricky, cause even when you don't make any money you still need to pay medical insurance and so. Oh and medical insurance is expensive in Germany. I pay about 190 euros per month and that's about as low as it gets, unless you're a student AND under 30.
Then, if you don't already speak German, I suggest you start learning. Best thing to do would be to take an intensive course. That of course is
expensive. I won't go into details, unless you're interested and ask me to.
Food is indeed cheap in Germany if you shop only at retailers such as Aldi and Lidl. Rents are cheap if you compare them to other countries from
Western Europe. However, in order to get an apartment you'll need to prove your income and to have a medical insurance and an occupation (student,
employed, volunteer, language school student, whatever). Unless you live with someone else who rents the apartment on their name.
Here's what I'd do if I were you: try to learn German and pass the TestDaf (an exam that will give you a certificate that you are able to speak
German at an academical level). Then try to get accepted to a German University. College education is free in Germany. Work hard and in about 4 years
you get a Bachelor from a German university which will open up a lot of possibilities for you. Just my advice.
Oh and move to a big city, Berlin or Hamburg, you have more options there!
Hope this helps...