German naturalization certificate - waiting period in your city?

You can only apply for German citizenship after having lived in Germany (without needing government handouts) for 8 years - or 7 years if you have integrated well into the society. Shorter periods are only possible in cases of severe hardship on a case-by-case basis.
Foreigner Authorities are overwhelmed by the number of foreigners almost anywhere, but you could try a smaller city in the Eastern provinces. You probably have to move there to be eligible to apply there.

I have been living in Germany for 10 years. Now I want to become a "digital nomad" and to travel around the world. But if I leave Germany, I am no more in a position to apply for German citizenship (8 years must be continuous). And so I want to get the dual citizenship as soon as possible.
This is an interesting official document with a comparison of timelines: https://www.muenchen-transparent.de/dokumente/4055561
Munich is exceptionally slow, 18 months. It's so frustrating. But Nuremberg seems to be good! I will try to apply from there, 3 months or 18 months - it makes a difference.

München  8 Monate + 10 Monate
Berlin (Bezirk Mitte)10 Monate + 6 Monate
Darmstadt wenige Tage + 3 Monate
Dortmund  1 Woche + 15 Monate
Düsseldorf 4 Monate + unbekannt
Essen 2 - 3 Wochen + 6 Monate(für einfache Fälle)
Hannover wenige Tage + 3 Monate
Nürnberg wenige Tage + 3 Monate
Stuttgart wenige Tage + 9 Monate