Running Ruby script on Notepad ++ using NppExec plugin

Hi my name is Lee I am new to the forums and Ruby programming.

I am trying to follow a tutorial on Ruby programming on youtube link:

I have searched the net for tutorials and sites explaining Ruby and feel
this tutorial is a good one to start with, I have followed the links on
the ruby-lang website such as tryruby but like the idea of being able to
execute a program I create

I have installed the Nppexec plugin and executed ruby
$(FULL_CURRENT_PATH) command but am not getting the program to run the
way in the tutorial at 3:00 minutes in.

Im not getting “Enter a value” come up just

ruby C:\new_1.rb
Process started >>>

Type in print and it just says

enter a value: enter another value: 0 + 0 = 0 <<< Process finished.
(Exit code 0)
================ READY ================

If I try enter a value such as 2 it says

2
CreateProcess() failed with error code 2:
The system cannot find the file specified.

================ READY ================

I am hoping someone can help me as to why I cant get the program to
work?

The code I am writing is the exact same as in the tutorial, I can post
if needed