A ‣ Places where you can eat 
café: you can have a cup of tea / coffee and a snack there (e.g. a sandwich or a cake). They sometimes serve meals too (e.g. lunch, dinner).
restaurant: you go there for a meal; more expensive than a café.
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, for example burger and chips.
take-away: you buy a snack or a meal there and take it home to eat.
B ‣ In a restaurant

C ‣ Expressions
Waiter: Are you ready to order?
Customer: Yes, I’d like the steak, please.
Waiter: Would you like it with chips or new potatoes?
Customer: With chips, please.
Waiter: How would you like your steak – rare, medium or well-done?
Customer: Well-done, please.
Waiter: And what would you like to drink?
Customer: I’ll have a coke, please.
(later)
Waiter: Is everything all right?
Customer: Thank you, it’s delicious. [very good]
(later)
Customer: Could I have the bill, please?
Waiter: Yes, of course.