Restaurants do not open anywhere in France much before 7:30, maybe 7:00 but 8:00 to 9:00 is the prime dinner hour. There should be a number from which to choose on Sunday.

Too bad you arrive the day after the marvelous Uzès Saturday market. Maybe you´ll stay long enough to see it to following Saturday.

Sunday afternoon shopping options are going to be minimal, I might even say there are none. Make restaurant reservations for Sunday evening and go shopping the next morning. Restaurant Ten is open on Sunday (unless they are closed for August). It´s a great place to eat in the center of town.

Will you be renting a car? If so, presumably you can pick up food on your way from the airport to Uzès. Supermarkets around Nîmes shown on google maps appear to close at noon on Sundays but there will certainly be somewhere. And Uzès is not so small that there will be nothing open. For instance Carrefour in Uzès is open until 7 on some Sundays in August (you don't say which Sunday so look on the website https://www.carrefour.fr/magasin/uzes ). Look here for other markets around town.

I don't understand why you have to have groceries your first night when you arrive so late, can't you just go shopping the next day? If you really want coffee (I might), you can bring a little bit of that really easily. Otherwise I agree, just go out to dinner, you don't need to be cooking a big meal that night. I wuldn't want to anyway upon arrival.

I don't think you are going to find any grocery store open after about 1 pm (the Carrefour closes then). But I think there may be cafes/casual places or smaller shops open, at least a couple. And there are restaurants that open before 7:30.

The Nougatine boulangerie/patisserie may be open all afternoon, try that. It says they are open all afternoon until 7:30 pm (and they sell sandwiches).
https://www.pagesjaunes.fr/pros/06993465

This place opens for dinner at 7 and claims it is open every afternoon until 5, also
https://www.thefork.com/restaurant/l...-souris/526245

THis cafe also says it is open every day in the afternoon until 6 pm.
Les Terroirs - Restaurant Uzès

I just wouldn't worry about not having anything to eat if that is the concern.

While in Uzès, I highly recommend Comptoir du 7 (not open Sunday). Scroll toward bottom if just want to read about restaurant/

https://travelswithmaitaitom.com/cha...problems-uzes/