There are approximately 10,000,000 Belgians in Belgium (and some outside of course).
6,000,000 speak Flemish or Dutch, whatever you like, 4,000,000 speak French, and a small group of ± 70,000 to 80,000 speak German.
There are 4 linguisitc regions, Flanders (Dutch speaking), the French community (French), the German community (German) and the Bilingual Community of Brussels (both French and Dutch)
WIth the exeption of the German speaking and people in the Brussels community, both "big" linguistic groups are childish and nationalistic when it concerns their language in their "territory".
A complicated story.