I researched the 4 most commonly foreign languages spoken in Germany and they are;
- English: 56% of the population speak English.
- French: 15% of the population speak French.
- Russian: 5% of the population speak Russian.
- Turkish: 1.8% of the population speak Turkish.
Apparently if you are a native English speaker, it will take you approximately 750 hours to learn German. If you speak German and are a beginner, then it is possible with a commitment of 5 hours per day to learn the language in one year to an advanced level in Business English.
The fun factor here is that accents are easy to pick up if you have a good ear and you can sounds almost like a native speaker within a few months if you practice 15 to 30 minutes per day.
The most difficult language for native German speakers to learn is Hungarian due to the grammar rules and pronunciation. I would have assumed that it was Mandarin but allegedly is not.
More important than anything with languages, is to have fun learning your chosen language/s.