Here are two little subs - one gets the name from keyboard input and the other opens the txt and prints to screen. Very basic - grow from there.

sub getname{
    $filename = $_[0];
    print "Enter the name of the $filename: ";
    $x = <stdin>;
    chomp($x);
    return $x;    
}

sub printscreen{
    $input_file_name = $_[0];
    open(infile, "<$input_file_name");
    while(<infile>)
        {    
            $line = $_;            
            print "$line";
        }
}
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