can declare a "my" variable in any lexical scope. Well, ok but you can't use it outside of that scope. The OP's indenting is confusing to me. Your code works until you try to use $something outside of lexical scope.

#!/usr/bin/perl
use strict;
use warnings;

my $whatever;

if($whatever) {
   my $something = "here";
}
else {
   my $something = "there";
}

print "look I compiled $something\n";

__END__

Global symbol "$something" requires explicit package name (did you for
+get to declare "my $something"?) 
at Monks\Badcode.pl line 14.
Execution of Monks\Badcode.pl aborted due to compilation errors.

Process completed with exit code 255
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