For more details see how the HTML Sitemap for Magento 2 extension works.
Create a handy HTML sitemap just in a couple of clicks. Add multiple links like products, categories, CMS-pages as well as any additional links to make the sitemap as detailed as it can be. Include and exclude particular pages from the sitemap and easily customize the layout of each sitemap block. Normally, HTML Sitemap accessible at example.com/sitemap.html
Title - Specify the title for your HTML Site Map. The title will be displayed on the sitemap page.
Meta Description - Meta description is essential for Google to understand what the page is about.
Layout - Design your HTML Site Map page with a ‘Layout’ feature. Choose the layout from the following options:
Show Search Field - Enable or disable the search window on the HTML sitemap page.
Sorting Order - Specify the priority of the sitemap content Categories, Products, CMS pages, Landing pages with drag-and-drop. Therefore, Google will crawl the most important for you entities first.
Subheader - Specify a custom subheader for the CMS Pages block displayed on the sitemap.
Number of Columns - Select the number of columns for the CMS Pages block.
Include CMS Pages - Set the option to 'Yes' to show CMS pages on the sitemap.
Exclude CMS Pages - Select the pages that should be excluded from the sitemap.
Subheader - Indicate the subheader for the Categories block.
Include Categories - Set to 'Yes' to include categories in the sitemap.
Show As - You can display product categories either as a tree or as a list.
Number of Columns - Set the number of columns for the Categories block.
Split by First Letter - Set this option to 'Yes' to display corresponding letters for each column.
Hide Out Of Stock Products - If the option is enabled, out of stock items won't be included in the sitemap.
Maximum Products Displayed on Sitemap - Specify a maximum amount of products displayed in a sitemap.
Additional Links - This option lets you specify any links to store pages you need. Each new link should be specified from a new line like it's shown in the example.