how to call the php function while the page is getting load

Question

I need to call the php function while the page is getting load.

Means when I click a link or menu of the page Homepage.php, then it will redirect to the page called History.php. Here before loading the page History.php, it sholud call the function to get the data from the database.

Please spend your valuable time to answer this query. Thanks in advance.

Answer 1

Top of History.php:

<?php
    include('/path/to/php/program/with/function.php');
    the_function();