Adding pagination to custom post type archives

Adding pagination to custom archives.php

<?php
global $wp_query;
      
      // Make Pages work with the loop
      $paged = ( get_query_var( 'paged' ) ) ? get_query_var( 'paged' ) : 1;
			
      // Args
      $args = array(
		'post_type' => 'custom_post_type',
		'posts_per_page' => 8,
		 'paged' => $paged
	);
			
      // The Query
	$the_query = new WP_Query( $args );
      
      // Store the orignal global $wp_query object
	$original_query = $wp_query;
	$wp_query = $the_query;

	// The Loop
	if ( $the_query->have_posts() ) :
		while ( $the_query->have_posts() ) :
					$the_query->the_post(); ?>
          
          <div> loop stuff here </div>
          
     <?php endwhile; // End The Loop


        // Using https://wordpress.org/plugins/wp-paginate/
        // But could be standard pagination here
	if(function_exists('wp_paginate')):
		wp_paginate(); 
	endif;


// Restore original Post Data
wp_reset_postdata();
$wp_query = $original_query;

If we don't store the original query objecy then the pagination will always show 12 pages items.

If you see a 404 page when trying to view page 2, then you need to update the default wordpress show posts figure.