A beginner asks: How do I get a button to fire off a SELECT statement?

I'm very new to ASP.NET and am obviously laboring under several misconceptions about how to properly access SQLEXPRESS.  For my Ancient Greek and Latin students I am building a page for reviewing vocabulary.
First, from a set of check lists (asp:CheckBoxList) the student selects what word categories s/he wants to review: nouns, verbs, adjectives, etc. These choices become variables in the WHERE statement. (I'm still working on that, too.) Then the student clicks on a Submit button (asp:Button) that fires off the SELECT statement against the table. The table returns a set of words and definitions, with the word linked to one asp:Repeater control, the definition linked to a second asp:Repeater control. The student reviews the word, then clicks on a Definition button to see the word's definition in the second Repeater control. The Defintion button then becomes a Next button to call up the next Word/Definition row from the table.
So that's it: Three buttons, two ...