How to ask the user and resolve their numeric inputs?

I am absolute new in the use of unreal engine, can you help me to realize the next interface user?
Each button send me to a level with an interface where the user should enter two variables and there is a solution button that must be show the result on click…
I do not know how to associate the text box for show the result…
Can you help me please?

1 - Select the button
2 - on the details panel select “On Clicked”


3 - implement the logic: get the text inside the boxes, transform them into floats, do the operation (in this case I’m just adding them), and then set the result in the corresponding box: