About Unity Headless license!

There is very little information on this question on the internet, as this answer has no additional information and an empty answer Free License No Graphics

Can I create a separate application with free license to use on my server as Unity headless? Is there a problem with me creating a separate game using free license to use on my server?

Would it be more convenient for a separate game as a server, or would I create server scripts in my own game, excluding the idea of creating a separate game to act as a server?

Can someone help me?