Most places will come by once when you are eating and ask how everything is. This is a chance for you to order something else, complain about something, or get a refill on your drink. Some of the things they might say are:
"How is everything?"
"Is everything ok?"
"How is your dinner?"
"How is your lunch?"
"Are you guys doing ok?"
"Do you need anything else?"
When you are almost done with your meal, they might ask if you want some dessert.
"Would you like dessert today?"
"Would you like our dessert menu?"
"Would you like to order any dessert?"
"Any dessert for you today?"
"Would you like to hear our dessert special?"
If you are finished and want your bill, you can look for the server, make eye contact, and raise your hand. When they come by, ask them for the bill.