We stayed at Chaumont-sur-Loire and asked our kind hosts for the closest market. They told us it…read morewas about a mile away. Sort of helpful. Fortunately, the Casino market has some advertising along the way, although exact directions would have been nice. The market has your standard fare although you have to know a few things as a non-French person. Eggs are kept on a shelf, so very hard to find. Weigh the produce before going to the register. Keep a euro coin in your pocket so you can unlock a shopping cart (not unique to France). Buy lots of cheese, super reasonable. :-)
Anyway, hope this was helpful. This is definitely where you should pick up your basics and necessities.