European dining practices and cuisine vary significantly by country from that in the USA -- you may find it charming, or not -- but you will find it different.
Meal times:
In France, most people start the day with a quick bite to eat, then eat lunch between noon and 2:30 and then dinner at 8:00pm-9:00pm or later -- its' not terribly unusual for them to still be eating dinnner as midnight closes in.
Breakfast usually consists of coffee and a baguette. Tradition was for someone in the household to rise early, walk to the local boulangerie and purchase baguettes for the morning meal -- stiil a common practice. Today, however, you're just as likely to see someone on the Metro or walking down the street consuming a coffee in one hand and a baguette in the other on their way to work. Relatively few eat a full breakfast and donuts are never on the menu (they're reserved for a late afternoon snack or desert after dinner.)
Coffee (consumed throughout the day) is not like the coffee here in the States. The French prefer expresso style coffee -- dark and strong and in very small portions. Order a coffee in France and you will most likely end-up with two to three ounces of coffee in a small paper cup (similar to the size cups you might use at an office water cooler) or glass -- a "large" or "double" contains about half the amount of a small coffee at a place like 7-11 here in the US. The only places serving full cups like we are used to here in the US are Starbucks (which seem to be everywhere, at least in major cities) and MacDonald's. In a restaurant or cafe, you will typically be served be served as you sit at a table -- whereas, at a boulangerie it'll be a toss-up whether they make and serve the coffee or you use a self-service machine -- one thing you will never see is coffee in a carafe -- it's all fresh-brewed once you order. Cafe Americano is the closest you'll get to regular black coffee, typically with room for cream -- although in a few places Cafe Americano was prepared as coffee with warmed milk (cafe au lait style). Except in a sit-down restaurant, you will pay separately for each cup consumed (2-3 euros per cup). In boulangeries, there are a variety of machines, some you put your euros into a slot and then push a button to select the type of coffee you want, others you need to purchase a token that you put in the slot, and others, you pay the cashier and then are directed to the machine to make your choice -- pretty easy once you understand how it works.
Lunch can be as simple as a sandwich and beverage or as full-blown as a three or four course main meal -- for many in France, lunch is the primary meal of the day. At many restaurants, you will receive a slightly smaller portion at lunch for one-half to two-thirds the price of the same meal in the evening -- a pretty good deal. A large number of people in France have a drink or two at lunch (wine or beer) -- it's also not unusual for lunch to last an hour to an hour and a half or longer -- of course, you will also see office workers picking up a sandwich (from a cafe, deli or boulangerie) or galette (crepe) and sitting on a park bench having a quick lunch -- in either case, lunch is an "event" -- rarely will you see anyone eating lunch while walking down the street like we do in the States.
Except for American franchises, "fast-food " really doesn't exist in Europe -- the French, in general, distain the idea of "fast-food" -- and as far as I know there is not even a word for it in the French language -- for "take-out" or to go, you use the term "emporter" and that usually refers to things like whole pizzas, Chinese, deli meals, etc.... You can almost always find a pre-made sandwich, an apple, a candy bar, etc... at a mini-mart if you're hungry mid-day.
Dinner is usually eaten sometime after 7:00pm -- typically 8:00pm-9:00pm -- although I've been out in the evening and observed groups going into to a restaurant on a week night at 11:00pm for dinner. Many restaurants are open for lunch from 11:30-2:30pm, then close for the afternoon and don't re-open until 7:00pm. An evening meal, done French-style, will take a minimum of two to three hours. Unlike in the US where you are seated and a server appears almost immediately to take your drink order, you will wait -- eventually a server will appear, take your drink order and then you will wait -- dining in France is suposed to be a leisurely experience -- they will reappear with your drinks and may take your food order, then you will wait -- eventually your food will be served. Once you are finished dining, you will wait -- your server will not bring you your bill, you must catch the server's attention and request your bill -- it is considered rude to bring you your bill without it being requested (if you are ever immediately presented with a bill, it's almost guaranteed you are dining in a place catering solely to tourists). A typical French meal ends with desert or a small plate of three or four different cheeses.
Food:
French food is French food -- you either like it or you don't -- it is heavy on pork, beef and seafood -- if you have dietary restrictions, you can find something on the menu but you will have limited choices. French cuisine is also heavy on using all parts of the animal so if you are adventurous, you will find many dishes that you will not see in the US. French cuisine, while reknown for its use of sauces in cooking and presentation, is quite bland -- if you are looking for spicy, you will not find it unless you go into a non-French ethnic restaurant (ie., Asian and some Middle-Eastern). THe lack of salt and pepper in cooking is healthy but typically not all that tasty. Expect to be provided with normal condiments (black pepper may may need to be requested and show-up in a ramikin from the shaker in the kitchen; mustard, also requested, may arrive on a small plate and, no, they don't usually have anything like French's yellow mustard in France -- expect more of a stronger, Dijon style mustard).
For me, the boulangeries were the true star of French cuisine -- they have available a wide range of baked goods not normally encountered in the US even in so-called "French bakeries". In most places, the baguettes come in a variety of choices: Traditional, Classical, Olive-oil based, Rustic, Whole Wheat, Spelt, Multi-grain and a bunch of others that I don't reemmber -- and like in the US, boulangerie baked baguettes are far superior to mass-produced, grocery store baked baguettes. Hot baguettees, fresh out of the baking oven --- OMG! -- often they never made it back to the apartment!
The croissants from boulangeries, regardless of where you were -- far superior to those here in the States -- maybe it's the air or the water -- here in Colorado Sproings, Panera and La Boulangerie do a decent job but really can't compare -- and the chocolate and chocolate-almond croissants -- heavenly -- I got used to buying to at a time so I could have one as a treat later in the day.
Fruit-based (and in some areas, nut-based) delicacies were a constant temptation -- it was amazing what a French baker could do with apples, apricots, strawberries, cherries, blueberries, etc... and a few spices!
Miscellaneous:
It is totally acceptable to ask for a carton to take unfinished portions of your meal with you.
Opened bottles of wine can also go with you as long as they have a cork or are somehow temporarily sealed.
Sit-down restaurants/brasseries have toilets for their patrons, usually down the stairs in the basement -- basic, clean accomodations. Cafes, delis, boulangeries and small food places don't. Gas stations do have facilities, again for patrons.
Except in large restaurants in touristy areas, tipping is not expected but is appreciated -- a few euros or 5-10% of the bill is sufficient unless you feel the server went way above and beyond in making your dining experience exceptional. Again, tipping is optional in bars although appreciated -- a euro or two per round is plenty.
Except at popular or large restaurants in touristy areas, reservations for dinner are not usually necessary -- restaurants that are small family-run or in small villages can typically accomodate you without a reservation but there's nothing wrong in making them just to be sure (might be a challenge making the reservation if you don't speak at least some French -- once you're at the restaurant, there will likely be someone who speaks a tiny bit of English and with a little patience and a smile, you should be okay).
Most tourist attractions where there's an entry fee will have a cafe that's pretty decent -- other places, picnicing is an excellent option.
Not all restaruants have menus in English so brushing up on French "food" words might be a good idea. Touristy locations may have someone to semi-translate -- off the beaten-track, not so much.
The French are very proud of their cheeses (hundreds of varieties) and sausages (quite regional so if you find one you like, buy extra as you may not find it elsewhere).
Be aware -- French food preparation can be very regional so even if the dish goes by the same name, it can be quite different from one area to the next.
Cooking your own meals in France can be quite wonderful as farmers' markets with fresh produce and local delicacies are abundant from Spring to Fall, and the experience of shopping in an open air market may be one of your most "special" memories of France.
Ground black pepper in restaurants is frequently not pure black pepper but a blend of some kind, brownish-grey with a very earthy, organic taste -- try it before using on your food.