Tips on Customizing CBX Changelog & Release Note

How to Hide CBX Changelog & Release Note Admin Menus

function plt_hide_cbxchangelog_menus() {
	//Hide "Changelogs".
	remove_menu_page('edit.php?post_type=cbxchangelog');
	//Hide "Changelogs → Changelogs".
	remove_submenu_page('edit.php?post_type=cbxchangelog', 'edit.php?post_type=cbxchangelog');
	//Hide "Changelogs → Setting".
	remove_submenu_page('edit.php?post_type=cbxchangelog', 'cbxchangelog-settings');
	//Hide "Changelogs → Helps  Updates".
	remove_submenu_page('edit.php?post_type=cbxchangelog', 'cbxchangelog-support');
}

add_action('admin_menu', 'plt_hide_cbxchangelog_menus', 12);

Where do I put this code?

How to Hide CBX Changelog & Release Note Meta Boxes

function plt_hide_cbxchangelog_metaboxes() {
	$screen = get_current_screen();
	if ( !$screen ) {
		return;
	}

	//Hide the "Change Logs" meta box.
	remove_meta_box('cbxchangelog_metabox', $screen->id, 'normal');
	//Hide the "Shortcode" meta box.
	remove_meta_box('cbxchangelog_shortcode', $screen->id, 'side');
}

add_action('add_meta_boxes', 'plt_hide_cbxchangelog_metaboxes', 20);