No. Flemish is rather a collective name for all kinds of dialects in the Dutch-speaking area of Belgium. Dutch is one of the official languages in Belgium, alongside French and German. The Flemish government has stipulated where the Dutch language must be used. So the government speaks of 'the Dutch language', not, for instance, 'Flemish'. But there is then 'the Flemish Community' or 'the Flemish Parliament'.