Do you know how many people starve to death every year around the world?
Literal
Every-year, world [in-で] how-much's people [subject-が] are-starving-to-death [question-か] know-[polite-ていますか]?
どれほど ('how much,' 'to what degree') is a formal quantifier question. 餓死する ('to die of starvation') is a compact Sino-Japanese verb. The embedded question ends in か before 知っていますか ('do you know?'), with 知っている being the resultative 'is in the state of knowing.'