if ( !is_admin() ) {
	add_action('wp_print_styles', 'wpe_styles');
	add_action('init','wpe_scripts');
	function wpe_styles() {
	    $wpe_css_Url = WP_PLUGIN_URL . '/wp-estate/wp-estate.css';
	    $wpe_css_File = WP_PLUGIN_DIR . '/wp-estate/wp-estate.css';
	    if ( file_exists($wpe_css_File) ) {
	        wp_register_style('wpe_styles', $wpe_css_Url);
	        wp_enqueue_style( 'wpe_styles');
	    }
	}
	function wpe_scripts() {
		$wpe_scripts_Url = WP_PLUGIN_URL . '/wp-estate/wp-estate.js';
	    $wpe_scripts_File = WP_PLUGIN_DIR . '/wp-estate/wp-estate.js';
	    if ( file_exists($wpe_scripts_File) ) {
		wp_register_script('wpe_scripts',$wpe_scripts_Url, array('jquery'),'' );
  		wp_enqueue_script('wpe_scripts');
  		}
	}
}

Enqueue Script and Style to website head from a plugin

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