Somewhere in between your initial idea and settling on a research question, you'll need to do background research on how scholars in a particular subject area have discussed your topic. You may find background research in your textbook or class readings, academic books in the library's collection, or reference sources.
After you have an initial project idea and gathered some background and definitions, you can think deeper about the idea.
How do you move from a research question to searching in a database? You first have to pick out keywords from your research question.