I’m not sure I understand the essence of your question.
WordPress’s “permalinks” feature can rewrite URLs from, say, example.com/?p=1 to example.com/page or whatever you want. In reality, WordPress just generates the necessary Apache rewrite rules in the .htaccess file — it’s really the Apache webserver that does the actual rewriting. If you’re using any other web server (eg Nginx), you’ll have to take care of the equivalent rewrite rules for your particular web server software.
So, this is really your web server’s job, and your rewrite rules would typically go into the .htaccess file at the root of your site (if you’re running a WordPress with working PERMALINKS, then the .htaccess file exists already, and you’ll just have to add your custom rules to it).
If I completely misunderstood your question, please clarify what exactly you’re trying to accomplish.
Good luck!
