Speaking of exam preparation, first of all, past questions
And because it's simple is best, it's simple
You can see the PDF file of the past questions of the 2019 Center Test for University Admissions in Japan. The answer is pasted at the bottom of the past question PDF file.
You can change to a different problem by pressing the "Another problem" button.
Other Center Past Question App
"English", "Japanese", "Mathematics", "Science", "Geographical history", "Public citizens"
Please download it as it introduces.

The introductory video is a nursing past question app, but the usage is the same

Growing blog

https://nobiru.click/app/android/jp/005-2019-senntaqa.html