Boy, it's great getting a simple question with a simple answer. ;-)

Your question is very general. There's a ton of information in the area, so it's more a matter of sifting through it. The obvious place to start for Apache would be http://apache.org, and for mod_perl, http://perl.apache.org. Of course, a visit to O'Reilly couldn't hurt.

Two particularly useful books in my experience are, "Apache, the definitive guide", and "Writing Apache Modules with Perl and C", both from O'Reilly.

Beyond that, you'll have to be more specific with what you mean by "I wish to use perl on the web".