Provide Python program code and step$-$by$-$step explaination for the following question.

The basic functionality of data processing $($data initialization, data insertion$),$ should be done using Numpy library while the computation $($ML$)$ part should be done using Scikit$-$learn library as much as possible.

$1.$ The program asks the user for input N $($positive integer$)$ and reads it$.$

$2.$ Then the program asks the user for input k $($positive integer$)$ and reads it$.$

$3.$ hen the program asks the user to provide N $($x$,$ y$)$ points $($one by one$)$ and reads all of them: first: x value, then: y value for every point one by one. X and Y are the real numbers.

$4.$ In the end, the program asks the user for input X and outputs: the result $($Y$)$ of k$-$NN Regression if k $<=$ N$,$ or any error message otherwise.

$5.$ Additionally, provide the variance of labels in the training dataset.