In order confirmation email, you see billing address and shipping address, this address format based on html template of customer address configuration. But you want to add data which not a customer attribute or an address attribute, how can you do that? To do that you need to change Renderer class.
You want to add friendly URLs for your custom module like product URLs in Magento 2. This short tutorial will help you doing that. In Magento 2 database, there is one table to store data about url “url_rewrite”. This table map target_path and request_path.