@brazil2007 Almost all Flemish people I know that went to school before the 70s (even Flemish nationalists) speak proper French, but since from the late 60s onward Flemish universities started teaching in Dutch instead of French (around the same time as the Révolution tranquille in Québec), the level of French of the average Joe has been declining rapidly. I would say that the majority of Flemish youth these days would have trouble having a decent conversation with a francophone.
In Wallonia, they never really bothered learning Dutch, but a couple of years ago they started teaching it in primary school and some young Walloons are capable of expressing themselves in Dutch. Dutch is also starting to become more and more required for higher level jobs in Wallonia and not just Brussels.
At the time of the independence of Belgium, Brussels was almost completely Dutch-speaking (Brabantian dialect to be more exact, because people only started speaking standard Dutch in daily life until after the popularization of TV), but now you can’t really live/work in Brussels without knowing French, like in Montréal. Most francophones in Brussels don’t speak Dutch, but they are sending their kids to Dutch-speaking schools more often nowadays, especially immigrants.