"He does not", or, "he doesn't speak English" would be correct. It would never be 'he do not speak English,' as that is incorrect grammar.
Outsiders may or may not speak English. It depends on the individual's background, education, and exposure to the language.
yes, some of them speak english.
yes they did speak English
Some Russians may speak English, especially in urban areas and among younger generations. English is taught in schools as a foreign language, but proficiency levels can vary.
I will speak in english better
"I can't speak English!" in English is Non parlo l'inglese! ("I don't speak English!") in Italian.
Yes he can speak English but he prefers to speak spanish
Yes the Celts do speak English
Around 3% of Rwandans speak English as their first language, however, the overall percentage of English speakers in Rwanda is higher due to its status as an official language and its increasing importance in education and business.
They did not speak English they spoke Greek.
But I do speak English, you are obviously misinformed.