As the others have said, please use <code> tags to format your code and data. See How do I post a question effectively?, I know what I mean. Why don't you?, and Short, Self-Contained, Correct Example.

However, even looking at the code as far as it as is readable at the moment, it seems like your code doesn't match the data you've provided: /-number_of_SP_mem_supp\s(\d+)/g won't match any of the provided data. And the task you are describing sounds pretty straightforward, a read of perlintro (and perhaps perlrequick/perlretut) should give you all the information you need. But if you run into trouble, please feel free to ask here, making sure to follow the advice given in the above links.

use warnings;
use strict;

while ( my $line = <DATA> ) {
    if ( $line =~ /^foo/ ) {
        for my $x (1..3) {
            print "foo$x\n";
        }
    }
    else {
        print $line;
    }
}

__DATA__
hello
world
foo_
bar
[download]

Your question is illegible as posted. Please peruse Markup in the Monastery and add some <c> markers.

A variation on haukex's approach (assuming that guess about what you want is right):

>perl

use warnings;
use strict;

# use following statement (or similar) in real program:
# open my $fh, '<', 'actual_file_name' or die "opening: $!";
open my $fh, '<', \<<'EOD' or die "opening: $!";  # for demo only
hello
world
foo_
bar
foo
foox
baz
 foo_
foo_xyzzy
boff
EOD

LINE:
while (my $line = <$fh>) {

    if (my ($intro) = $line =~ m{ \A (foo) _ }xms) {
        print "$intro$_\n" for 1..3;
        next LINE;
        }

    print $line;

    }

^Z
hello
world
foo1
foo2
foo3
bar
foo
foox
baz
 foo_
foo1
foo2
foo3
boff
[download]

Also, please see the Short, Self-Contained, Correct Example article for ways to further clarify your question and its context. Please help us to help you.