One of the words that means 'to eat' is кушать. Theoretically one can say мы кушали пиццу 'we ate pizza.' But this word is not one that usually comes from the lips of a grown man. It's a word used by Mama and Gramma when calling people to the table by saying идите кушать, or they might ask if you want to eat by saying вы кушать будете? But even when Mama and Gramma say it there is something domestic, affectionate or cuteish about it.
There is also an old fashioned language rule that says you should never use the verb кушать in the first person.
If you want to ask if someone wants to eat, the most neutral way is to say Будешь есть/завтракать/обедать/ужинать? Cruder versions are Будешь жрать? Будешь хавать? (The хавать version is a Belarusian influence.)
The word стол means 'table.' It is one of the first words taught in Russian classes because it is short, easy to pronounce, and has perfectly regular grammatical endings. It is also the classic word used when practicing noun declensions: it's common to hear Russian students chanting стол, стола, столу, стол, столом, столе in the course of their studies. Declining стол out loud gives the good Russian student the same pleasure that a good piano student gets when practicing scales. Sure, it's a simple thing to do, but it shows a type of mastery.
There are two different patterns common to declining Russian nouns. The chant shown above follows the classical order that is used in reference books in Russia and in more traditional textbooks in the United States. There is a also another pattern, the 'linguistic' pattern, that is used by historical linguists and by newer textbooks. The newer system is better pedagogically because it illustrates the generalizations of noun declension in a neater fashion. You can see the two patterns contrasted here.
The phrase письменный стол means 'desk, writing table.'