In Britain you often have three courses: a starter (e.g. soup), a main course (e.g. steak or chicken) and a dessert (e.g. strawberries or ice cream). You may also have an aperitif (a drink before the meal, e.g. gin and tonic) and coffee after the meal. When you pay the bill (the money for the meal; AmEng: check) you sometimes also leave a tip for the waiter if service is not included in the price (10% is a normal tip). If it is a popular restaurant, you may also need to book (reserve) a table in advance (before you go).
Places where you can eat
cafe: you can have a cup od coffee or tea and a snack there (e.g.) a sandwich or a cake); they sometimes serve meals (e.g. lunch, dinner) too;
restaurant: you go there for a meal; more expensive than a cafe;
bar/pub: bars and pubs serve alcohol and soft drinks [non-alcoholic drinks, e.g. fruit juice]; you can usually have a meal or a snack there too;
fast food restaurant: you can get a quick hot meal there. e.g. burger and chips;
take-away: you buy a snack or a meal and take it home to eat;