Hi foO,
If I understand you correctly you guessed right why @t is empty because you needed to escape the fullstop (dot ".") in split. Try something like this:

#!/usr/bin/perl -w
use strict;

my $ip = "192.168.2.34";
my @t = split(/\./, $ip);
my $x = @t;

print "Number of elements in array: $x\n";
print "Content of array: @t\n";
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As a beginner now would be a good time to learn to use strict and warnings (-w flag after shebang). These are handy tools for debugging your future scripts.

update: changed text slightly because the node got retitled.