Tips on Customizing Post Grid and Gutenberg Blocks

How to Hide Post Grid Gutenberg Blocks Admin Menus

function plt_hide_post_grid_menus() {
	//Hide "Combo Blocks".
	remove_menu_page('post-grid');
	//Hide "Combo Blocks → All Post Grid".
	remove_submenu_page('post-grid', 'edit.php?post_type=post_grid');
	//Hide "Combo Blocks → All Saved Templates".
	remove_submenu_page('post-grid', 'edit.php?post_type=post_grid_template');
	//Hide "Combo Blocks → All Saved Layouts".
	remove_submenu_page('post-grid', 'edit.php?post_type=post_grid_layout');
	//Hide "Combo Blocks → Create New".
	remove_submenu_page('post-grid', 'post-new.php?post_type=post_grid');
	//Hide "Combo Blocks → Import Layouts".
	remove_submenu_page('post-grid', 'import_layouts');
	//Hide "Combo Blocks → Settings".
	remove_submenu_page('post-grid', 'post-grid-settings');
	//Hide "Combo Blocks → Dashboard".
	remove_submenu_page('post-grid', 'post-grid-dashboard');
	//Hide "Combo Blocks → Overview".
	remove_submenu_page('post-grid', 'post-grid-overview');
}

add_action('admin_menu', 'plt_hide_post_grid_menus', 11);

Where do I put this code?

How to Hide Post Grid Gutenberg Blocks Meta Boxes

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

	//Hide the "Post Grid - Post Options" meta box.
	remove_meta_box('post-grid-post-option', $screen->id, 'normal');
	//Hide the "Post Grid Options" meta box.
	remove_meta_box('post-grid', $screen->id, 'normal');
	//Hide the "Post Grid Info" meta box.
	remove_meta_box('post-grid-side', $screen->id, 'side');
	//Hide the "Layout data" meta box.
	remove_meta_box('post-grid-layout', $screen->id, 'normal');
}

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