Code:
use strict;
use warnings;

open my $F1, '<', 'testing.txt' or die "failed $!";
open my $F2, '>', 'out.txt' or die "failed $!";

while (<$F1>) {
if (/^\$ NAME : sandy/../\$.TO/) {
print $F2 $_;
}
if (/^\$ NAME : patrick/../\$.EON/) {
if(/^G1/../\$SRU){
 s/G1/G1.G1o.n/g;
print $F2 $_;}
}

 }
close $F1;
close $F2;