@dekkosecure,
All sites on WordPress.com have default hosting and SSL Certifications taken care for you. You cannot change, or modify that with WordPress.com, or edit any files. You can only do that on self-hosted sites.
There isn’t any plugins that will allow you to do this on WordPress.com, and you’d have to be on the Business plan, and you would possibly mess up your site if there is a plugin that lets you do that which isn’t recommended. Let me know if you have any further questions.
