Welcome Grzegorz.
This tutorial shows one way to make a quiz using lists App Inventor Tutorials and Examples: Advanced Features | Pura Vida Apps .
It gives you a possible starting point. Lists can be saved as Tags in FirebaseDB and CloudDB. You have more database options too that are more complex ( see Multiple choice quiz retrieving questions and answers from google sheets or csv - #3 by TIMAI2 ) to get some ideas.
Here are some resources to help you learn to use the AI2 tools. A very good way to learn App Inventor is to read the free Inventor's Manual here in the AI2 free online eBook http://www.appinventor.org/book2 ... the links are at the bottom of the Web page. The book 'teaches' users how to program with AI2 blocks.
There is a free programming course here http://www.appinventor.org/content/CourseInABox/Intro and the aia files for the projects in the book are here: http://www.appinventor.org/bookFiles
How to do a lot of basic things with App Inventor are described here: http://www.appinventor.org/content/howDoYou/eventHandling .
Also look here App inventor español. Offline. Tutorial. Ejemplos. Instalación. Códigos. Juegos. Curso gratis de App inventor. and here Tutorial Index | imagnity for more tutorials
Learn about components Component Reference
and visit the Library The MIT App Inventor Library: Documentation & Support Help>Library on the MENU