Launcher References Object Variable

So I set out to write a program that takes two things from user: Name and Age

Then prints out "Name is Age"

I went through using a "launcher" and having a proper object: [URL]

The class names are Practice and Practice Launcher because I just use a Practice file as a sandbox environment so I understand its not correctly named. I also understand my comments aren't great but I'm just trying to make it work.

Practice.java
public class Practice {
//constructor
public Practice (String a, int b) {

[Code]....

My Practice.userName doesnt reference the variable userName. Why is this?

Also y does this line need Practice twice?
Practice Practice = new Practice(userName, 45);