Scratch

Background information if you are wondering what this is about...
I have to make a game for my assignment at school and im not sure on how to go about this because im new to this.

I would like to make a game for my little cousin to help him with his school work, called build the castle. He wants it to be about building a castle to the very top e.g. 6 square blocks stacked to make a pyramid trangle shaped castle.

however there are number equations inside the blocks e.g. (10 divided by 2).

Questions
******How do I make scratch  bring up a text box to type the answer in and if the answer is right add a point to varible +1 to :*(Score) I made?******

******Also if it isn't too much trouble how do you make it if the answer is wrong (i.e. number other than the set answer) restart the entire game?

I would be very happy and it would make my day if anyone can offer some solutions to this problem i have.
Thanks Jebis

ill post more questions later about the game development, but for now I just need to solve this