Do you speak English? = Sprichst Du Englisch? (informal)
Do you speak English? = Sprechen Sie Englisch? (formal)
Do you speak English is Sprechen Sie Englisch in German.
The correct spelling is
Können Sie Deutsch sprechen?
Sprechen Sie Französisch?
Does he speak German = Spricht er Deutsch
In Germany you speak usually the German language.
No she doesn't speak German.
How do you speak German = Wie spricht man Deutsch
They are German so they speak German to each other.
People in Vienna speak Viennese German.
No, sprechen means speak in German.
Does he speak German = Spricht er Deutsch
There are gnomes that speak German fluently because they are german. Or they simply studied it.
"Do you speak in German" is "Sprechen Sie Deutsch?" (formal) or "Sprichst du Deutsch?" (informal) in German.
German is not the official language in Estonia, but some Estonians surely know how to speak German.
It would be most unusual for a German not to be able to speak German. I therefore answer 99.99% of Germans speak German. The reasoning :- there is a very small percentage of people who have speech impediments that rends it impossible for them to speak at all.