Your Floranext site has built-in search engine optimization. When your site is created it automatically has search engine keywords, metatags, and title tags set. However you can change all of these in your Admin Dashboard by going to Settings > Website Settings. (bottom of page SEO Section)
Here are some basics about Search Engine tags:
Title Tag - this is the page name that shows up on search results. In your Floranext site this is automatically generated -- on the home page this is just your Store Info tab under "Search Engine Title". The home page will show up as "Search Engine Title" For product pages, they will appear in the format "Product Name | Search Engine Title."
Search Engine Description - This is the description that appears under the title tag on search engine results.
Search Engine Keywords - Keywords don't show to the users or on search engine results. These are for search engine "spiders" that read your website to help with categorization. Most SEO experts agree this information is less important these days and that the content on your website that is visible to users is more important.
H1 & H2 - The header tags help search engines understand what your website is about. For more information how header tags work please review the following article