View all posts of a custom type

Not sure if this is what you are asking but, I have two custom post types on my website, and the URL to view all posts of a custom post type is edit.php?post_type=mp_shortcodes

If you replace mp_shortcodes with your custom type it might allow you to view all the posts for that custom post type.

See if either of these two help you.

To use this plugin, create a new folder in your WordPress installation’s wp-content/plugins directory and name it something like custom-post-type-listing. Then, create a new PHP file named custom-post-type-listing.php inside that folder and copy the code above into it.

After activating the plugin through the WordPress admin panel, you’ll see a new menu item named “Custom Post Types” under the “Dashboard” menu.

Don’t install at the same time.

<?php
/*
Plugin Name: Custom Post Type Listing
Plugin URI: https://www.example.com/
Description: A plugin to list all custom post types and their posts.
Version: 1.0
Author: Your Name
Author URI: https://www.example.com/
License: GPL2
*/

// Hook into the admin menu to add a custom page for displaying custom post types
add_action( 'admin_menu', 'cpt_listing_add_menu' );

function cpt_listing_add_menu() {
    add_menu_page(
        'Custom Post Types',
        'Custom Post Types',
        'manage_options',
        'cpt-listing',
        'cpt_listing_page',
        'dashicons-admin-post',
        25
    );
}

// The callback function for rendering the custom post type listing page
function cpt_listing_page() {
    $post_types = get_post_types( array( 'public' => true ), 'objects' );

    // Output the custom post types and their posts
    echo '<div class="wrap">';
    echo '<h1>Custom Post Types and Posts</h1>';

    foreach ( $post_types as $post_type ) {
        echo '<h2>' . esc_html( $post_type->label ) . '</h2>';

        $args = array(
            'post_type'      => $post_type->name,
            'posts_per_page' => -1,
        );

        $query = new WP_Query( $args );

        if ( $query->have_posts() ) {
            echo '<ul>';

            while ( $query->have_posts() ) {
                $query->the_post();
                echo '<li>' . get_the_title() . ' | ' . esc_html( $post_type->name ) . '</li>';
            }

            echo '</ul>';
        } else {
            echo '<p>No posts found.</p>';
        }

        wp_reset_postdata();
    }

    echo '</div>';
}

<?php
/*
Plugin Name: Custom Post Type Listing
Plugin URI: https://www.example.com/
Description: A plugin to list all custom post types and their posts.
Version: 1.0
Author: Your Name
Author URI: https://www.example.com/
License: GPL2
*/

// Hook into the admin menu to add a custom page for displaying custom post types
add_action( 'admin_menu', 'cpt_listing_add_menu' );

function cpt_listing_add_menu() {
    add_menu_page(
        'Custom Post Types',
        'Custom Post Types',
        'manage_options',
        'cpt-listing',
        'cpt_listing_page',
        'dashicons-admin-post',
        25
    );
}

// The callback function for rendering the custom post type listing page
function cpt_listing_page() {
    $post_types = get_post_types( array( 'public' => true ), 'objects' );

    // Output the custom post types and their posts
    echo '<div class="wrap">';
    echo '<h1>Custom Post Types and Posts</h1>';

    foreach ( $post_types as $post_type ) {
        echo '<h2>' . esc_html( $post_type->label ) . '</h2>';
        $post_type_url = 'edit.php?post_type=' . $post_type->name;
        echo '<a href="' . esc_url( $post_type_url ) . '">View All ' . esc_html( $post_type->label ) . '</a><br>';
    }

    echo '</div>';
}