How to add your application to ports or create a pkg package?

Question

FreeBSD

There is an application source and freebsd 11.1
You need to create a package for subsequent installation via pkg.
I understood from the documentation that pkg create creates a package based on ports. Therefore, the question arises, how to put the program into the ports, so that later we can assemble the package?

Answer 1

Write a port :)
Here in the "Publications" section there are a couple of articles on the topic of creating a port. The article is quite old, but nothing has changed in the general mechanics of the process of creating and publishing the port, only the tools could change.

Answer 2

Read primary sources:
In English
In Russian (I admit that traditionally it is slightly behind the time of the English language)