Related questions and search terms for this same question are:
Can I SEO optimize these themes?
Are the themes SEO optimized?
Each theme is pre configured with SEO in mind. That is, you will find various configurations through out the site that will help in optimizing the pages (for example it allows you to configure the type of headings you want to use) and content for getting indexed in Google (for example the content listed on the homepage). Note though, that this is a just a starting point for optimizing your site. We recommend to further optimize the website once you have installed the turnkey content. The first step would be to install and activate the so called "WordPress SEO" plugin by Yoast (aka the Yoast plugin). The plugin itself is free (you can download it from here; https://wordpress.org/plugins/wordpress-seo/). For a complete list of SEO related questions and answers please see the following page; https://www.wpsupporthelp.com/wordpress-questions/seo-wordpress-questions-89/
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