If the theme and app are Online Store 2.0 compatible, you can use theme app extensions to embed the quiz where you want in your theme.
How to do it? it's very easy.
1. Go to the Onlline Store > Themes
2. click on Customize
3. Go to the Page you would like to add the quiz on, and add any section or block. scroll down, and you will see our app icon. add it and it will appear on the location you choose 🎉