Given count.pl that looks like this:

C:\test>type count.pl
#! perl -slw
use strict;
use 5.010;

say for 1 .. 1e6;
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You can run that script using this script:

#! perl -slw
use strict;
use Win32::Process;

Win32::Process::Create(
    my $hProc,
    '/perl64/bin/perl.exe',
    'perl count.pl',
    0,
    0,
    '.'
) or die $^E;

my $state = 1;
while( <STDIN> ) {
    if( $state ) {
        $hProc->Suspend();
        $state = 0;
    }
    else {
        $hProc->Resume();
        $state = 1;
    }
    print "\nProcess is ", $state ? 'running' : 'suspended';
}
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And each time you press enter on the command line, count.pl will be suspended or resumed.