In France, a meal is as much a ceremony as it is a necessity. Though the French enjoy food greatly, they also take it seriously, and treat the ceremonies of mealtime with respect.
For instance, the maitre-d' will welcome you and find you a suitable table; your waiter will be a professional, always polite, always efficient. The chef will be good and careful in his or her work. This is their obligation to you and also their professional pleasure.
The part you play in the ceremony is equally important, and it is expected that you will play your part properly.
Play the game by the rules to receive good service. Always treat restaurant personnel like professionals, for that's what they are. Be formal and polite, and try to do things the French way. (In France, serving in restaurants and cafes is not a job done by those waiting to find other jobs, it is done as a lifetime career.)
To call the waiter, say "Monsieur" (not "Garçon") or "Madamoiselle" or "Madame," as appropriate.
Learn the rules of French dining: cocktails (aperitif) are drunk only before dinner, never at the table with a meal. Coffee is drunk only after dessert, never with a meal. This may not be your preference, but these are the French rules of the ceremony, and if you order coffee at the beginning of lunch or dinner, even in an informal café, it will br brought after the meal anyway.