Cheap Shopping in Brussels

Hello! I just moved to Brussels yesterday & have been struggling to find some reasonably-priced grocery stores/shopping in general. Is there anywhere that you would recommend to shop, that doesn't cost a fortune? I'm living pretty close to the center, but have gotten a transportation card..

Thank you!

p.s. - somewhat irrelevant, but does anyone recommend a good place to learn some basic French? I will only be here over summer, and would rather learn the speaking aspect, just so I can communicate more efficiently. :)