Check out example codes for "wordpress have_posts not working". It will help you in understanding the concepts better.

Code Example 1

//As per my understandings of your issue:

//You are not querying posts you need to show. Use wp_query() to query your posts before loop.

$wp_query = new WP_Query(array('posts_per_page'=>-1));
while ($wp_query->have_posts()) : $wp_query->the_post();
    //your code here

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