welcome to PM and perl!

You'll find that the Tutorials section here has a lot of good starting points, including this one that walks through making a print "Hello, World!\n" script: Perl Babysteps 1: Your First Simple Script

Your problem most likely is that the file isn't named 'hello' or doesn't have the proper permissions .. this tutorial has pointers for that type of issue: The basics

Also be sure to have a look at Writeup Formatting Tips in order to get the most out of your questions here (the easier/more standard they are formatted, they better/faster people will answer)