Tips on Customizing Popup Maker – Popup for opt-ins, lead gen, & more

How to Hide Popup Maker Admin Menus

function plt_hide_popup_maker_menus() {
	//Hide "Appearance → Popup Themes".
	remove_submenu_page('themes.php', 'edit.php?post_type=popup_theme');

	//Hide "Popup Maker".
	remove_menu_page('edit.php?post_type=popup');
	//Hide "Popup Maker → All Popups".
	remove_submenu_page('edit.php?post_type=popup', 'edit.php?post_type=popup');
	//Hide "Popup Maker → Create Popup".
	remove_submenu_page('edit.php?post_type=popup', 'post-new.php?post_type=popup');
	//Hide "Popup Maker → Popup Themes".
	remove_submenu_page('edit.php?post_type=popup', 'edit.php?post_type=popup_theme');
	//Hide "Popup Maker → Subscribers".
	remove_submenu_page('edit.php?post_type=popup', 'pum-subscribers');
	//Hide "Popup Maker → Upgrade".
	remove_submenu_page('edit.php?post_type=popup', 'pum-extensions');
	//Hide "Popup Maker → Settings".
	remove_submenu_page('edit.php?post_type=popup', 'pum-settings');
	//Hide "Popup Maker → Tools".
	remove_submenu_page('edit.php?post_type=popup', 'pum-tools');
	//Hide "Popup Maker → Help & Support".
	remove_submenu_page('edit.php?post_type=popup', 'pum-support');
}

add_action('admin_menu', 'plt_hide_popup_maker_menus', 1000);

Where do I put this code?

How to Hide Popup Maker Meta Boxes

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

	//Hide the "Popup Settings" meta box.
	remove_meta_box('pum_popup_settings', $screen->id, 'normal');
	//Hide the "Analytics" meta box.
	remove_meta_box('pum_popup_analytics', $screen->id, 'side');
	//Hide the "Theme Settings" meta box.
	remove_meta_box('pum_theme_settings', $screen->id, 'normal');
	//Hide the "Theme Preview" meta box.
	remove_meta_box('pum_theme_preview', $screen->id, 'side');
}

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