Starting small is not too hard. Here is module Foo.pm:

package Foo;
require Exporter;
 
@ISA = qw|Exporter|;
@EXPORT_OK = qw|foo|;
 
sub foo
{
   print "Hello World\n";
}
 
1;
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And here is how it is used:

use Foo foo;

foo();
print "Goodbye\n";
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Simplicity itself: we mark the routine  foo() as exportable and import it with  use Foo foo;.

The complexity you saw comes if you want to package up your module as a full blown library worthy of CPAN. For that you will want to read perlman:perlmod to see how modules work and perlman:perlmodlib to see how to create them. Also check out perlnewmod for preparing a new module for distribution.

-Mark