How to structure/store my data

Hi guys, so my app is a learning/practice platform for accounting students to exercise what they learned in class. And i have a few questions:

I want my app to display a question (formatted as a table/grid) and allow the user to insert text and numbers inside the cells. With a click of a button, i want the system to display the correct answer to the user. I also want to indicate the right and wrong answers using colors. they will fill the cell accordingly red or green.

How should i go about storing the correct answers in my apps data base?
Also, i’m looking for more info on how should i build my app’s logic in my case in a way that doesn’t slow my app - I’d appreciate some guidance.
One thing to consider is that I will have more than 200 questions on the site so i need a simple way to store the answers. I will add more questions as time goes and i need a simple process i can repeat.

Sorry if i sound a little unclear, as a newbie im not sure im using the correct terms.
Thank you all