The loop will not loop

Hi!

What I want is pretty easy. I have a page which shall simply display the loop (all entries). I spent hours reading the documentation. There it says that
<?php if (have_posts()) : while (have_posts()) : the_post();?>
should do the job. It did not. From other places I basically learned I have to kind of initiate it. So I added the following above:

<?php $args=array(
    'posts_per_page' => 2
  );
  $wp_query = null;
  $wp_query = new WP_Query($args); ?>

This now works as expected. Well, not quite. I also have the link for previous entries displayed. This appends /page/2/ to the URL of my page. But it does not do what it should do. I assume it has to do with what I entered above.

So what’s wrong? Where is the simple documentation for: “How to display the loop in a page?”

Thanks
pi