Looks like you have to write a console application.
Ok, you’ve chozen it to be a quiz. No, do some analysis of the problem. What will be the subject of the quiz? What kinds of questions you’ll have? In what form the answers will be given (a number, a selection from a list of options, yes/no, a word etc.)? So, you’ll get a set of entities that your app should deal with. These entities will become base classes for your app. The user interface could be quite simple, like printing a question to the console and reading input back.
Gradually working on this task you can master many aspects of OOP.