Here is the problem:
"Write a program that asks the user to enter a number.
Then it outputs the multiplication table for this number.
Sp, e.g. if the user enters 3, the programs outputs
You've got the basic structure alright; but you aren't outputting anything. You just need a cout statement in your loop. You just need to output the current iteration (i), the entered number (n) and the product of the two (i*n), along with some formatting.
You also need to remove the ";" after your while statement, and also your "do" and second while statement.