WordPress is fetching current post for you, you have to only type to the right url. When you get e.g. to example.com/lorem-ipsum/ WordPress will load automatically post with title Lorem ipsum and display it using page.php template. Your page.php template should be looking something like that.
<?php get_header(); ?>
<div id="content">
<?php while ( have_posts() ) : the_post(): ?>
<h1><?php the_title(); ?></h1>
<?php the_content(); ?>
<?php endwhile; ?>
</div>
<?php
get_sidebar();
get_footer();
The concept of a loop is difficult to understand for novice developers. Only in the loop you can use functions like the_title orthe_content. Outside of the loop, these functions won’t return you anything.