You could either use a plugin like PHP Exec, which allows you to put PHP code directly into a page, or create a custom page template, and in the template file for that page, either add your PHP code directly, or just have it include lol.php
I prefer the custom page template method myself, and it is very easy to do.
You basically just duplicate your template’s page.php file, call it something like page-lol.php, and add a header like this:
Template Name: lol
Then when editing your page, just specify the page template to use.