please help!!!!

[Amira Samir]

required :The game starts by showing the user a number of cards on the screen. Each card is represented by a character ‘C’. Then, the computer chooses a random card and tells the user to remember its position number. Some swaps between cards are made, and then the computer asks the user to enter where the chosen card should be after swapping. If the user guessed it right, then a “congratulations” message should appear, if not, a try again message should appear.
My problems are how to make the letters exchange in front of the user, how to make the letter which has the value of the king appear and disappear, and that the console screen clears when the user press on any key.......