In Paris 2nd. Arr.

Brasserie Dubillot is quite good for French cuisine in a modernized traditional environment. Good value, too.
In a completely different vein, I have few points of comparison but I greatly enjoyed a Ukranian meal at Oranta, right by the Opéra Comique.
Around rue Sainte Anne, you have dozens of Japanese restaurants. I am not a huge fan of that cuisine in general, but many people swear by some of the ramen places there.
Overall, there are TONS of restaurants in the area, so you will not starve 😅.

Le Comptoir de la Gastronomie on Rue Montmartre is not in the 2nd but is very close to the southeastern part of the 2nd is good especially for those who like foie gras. Tigermilk Sentier on Rue d'Aboukir is good. They say it's Latin American food, but I think it is more Peruvian. I have not been yet but I plan to take my niece who is a vegan to Kapunka Vegan Thai on Rue de Damiette. Their non-vegan but gluten free Thai, Kapunka Montorgeuil on Rue Saint Sauveur is very good. If you like cocktails, check out the Experimental Cocktail Club on the same street.

Le Mesturet on the rue Richelieu is a reliable address. It’s not fancy, more a neighborhood restaurant. But the food is made in house and is good.

Ooh, I forgot about Le Mesturet. Excellent suggestion.