How to give Capabilities to a Custom Role for a Custom Post Type

I am trying to give my custom role 'Student" capabilities so they can work with the custom post type 'Event'. With my current code the custom role can only "view" all the custom post types and has no other power, even though I have add capabilities specifically for the 'Event' custom post type. I have added the custom role using a plugin and the custom post type code lies in the functions.php. Here's my code:

Custom Post Type:

function mepoNET_post_types() {
            register_post_type('event', array(
                'public'            => true,
                'labels'            => array(
                    'name'          => 'Events',
                    'add_new_item'  => 'Add New Event',
                    'edit_item'     => 'Edit Event',
                    'all_items'     => 'All Events',
                    'singular_name' => 'Event'
                ),
                'menu_icon'         =>'dashicons-calendar-alt',
                'supports'          => array( 'title', 'editor', 'author', 'thumbnail', 'excerpt', 'comments' ),
                'show_in_rest'      => true,
                'taxonomies'        => array( 'category', 'post_tag' ),
                'has_archive'       => true,
                'capabilities'      => array('event', 'events'),
                'map_meta_cap'      => true,
            ));
}
        
        add_action('init', 'mepoNET_post_types');

Custom Roles Plugin:

 
 defined('ABSPATH') or die();

 
 register_activation_hook(__FILE__,'mepoNET_roles_activaton');


register_deactivation_hook(__FILE__,'mepoNET_roles_deactivaton');

 function mepoNET_roles_activaton(){
    $caps =[
        'read'         => true,
        'edit_posts'   => true,
        'upload_files' => true
    ];

    add_role('mepo_student', 'Student', $caps);
 }

function mepoNET_roles_deactivaton(){
    remove_role('mepo_student');
}

add_action('admin_init', 'mepoNET_add_role_caps', 999);

function mepoNET_add_role_caps(){
    $student = get_role( 'mepo_student' );

    $student->add_cap( 'edit_event' ); 
    $student->add_cap( 'edit_events' ); 
    $student->add_cap( 'read_event' ); 
    $student->add_cap( 'delete_event' ); 
    $student->add_cap( 'publish_events' ); 
    $student->add_cap( 'read_private_event' ); 
    $student->add_cap( 'delete_event' ); 
}

@onlyoreoo,

By default registering a custom post type is set to post, which means you would have to give the role permission to edit a post. If you want to keep posts/blogs and the new custom post type separate, you have to add this line to the registration of the custom post type 'capability_type' => 'event',

Your code should look like this.

function mepoNET_post_types() {
            register_post_type('event', array(
                'public'            => true,
                'labels'            => array(
                    'name'          => 'Events',
                    'add_new_item'  => 'Add New Event',
                    'edit_item'     => 'Edit Event',
                    'all_items'     => 'All Events',
                    'singular_name' => 'Event'
                ),
                'menu_icon'         =>'dashicons-calendar-alt',
                'supports'          => array( 'title', 'editor', 'author', 'thumbnail', 'excerpt', 'comments' ),
                'show_in_rest'      => true,
                'taxonomies'        => array( 'category', 'post_tag' ),
                'has_archive'       => true,
                'capability_type'   => 'event',
				'capabilities'      => array(
					'edit_events' => true,
					'read_events' => true,
					'delete_events' => true,
					'publish_events' => true,
					),
                'map_meta_cap'      => true,
            ));
}
        
        add_action('init', 'mepoNET_post_types');

The registration for the new role should look like this:

function mepoNET_roles_activaton() {
		add_role(
			'mepo_student',
			'Student',
			array(
				'edit_events' => true,
				'read_events' => true,
				'delete_events' => true,
				'publish_events' => true,
				'read_private_events' => true,
				'delete_events' => true,
				'read' => true,
				'edit_posts' => false,
				'delete_posts' => false,
				'publish_posts' => false,
				'upload_files' => true, // only add this if you want the students to be able to add images/files
			),
		);
	}

Dashboard should look like this:

Hope this helps.

Reference list of all Roles and Capabilities:

https://wordpress.org/documentation/article/roles-and-capabilities/