Hi As Below path i have added code ,
app\design\frontend\Magento\luma\Magento_Theme\layout\default_head_blocks.xml
<?xml version="1.0"?>
<page xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:View/Layout/etc/page_configuration.xsd">
<head>
<meta name="viewport" content="width=device-width, initial-scale=1, maximum-scale=1.0, user-scalable=no"/>
<meta charset="utf-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<css src="css/styles-m.css"/>
<css src="css/styles-l.css" media="screen and (min-width: 768px)"/>
<css src="css/print.css" media="print"/>
<css src="Magento_Catalog::css/custom.css"/>
<css src="Magento_Catalog::css/responsive.css"/>
<css src="Magento_Catalog::css/owl.carousel.css"/>
<css src="Magento_Catalog::css/owl.carousel.theme.css"/>
<css src="Magento_Catalog::css/font-awesome.min.css"/>
<!--<script src="Magento_Catalog::js/jquery-1.12.2.min.js"></script>-->
<script src="Magento_Catalog::js/owl.carousel.js"></script>
<script src="Magento_Catalog::js/custom.js"></script>
<link src="https://fonts.googleapis.com/css?family=Lato:400,700,900" src_type="url" />
</head>
</page>
Also CSS And JS File As Below Path
app\design\frontend\Magento\luma\web\css
app\design\frontend\Magento\luma\web\js
After run command as
php bin/magento cache:clean
php bin/magento setup:static-content:deploy
Now On frontend no show me file .please help .