Not a smart question:
Can I delivery content of paid unitypackage form Asset Store as part on my freeunitypackage?
But I need an smart answer:
What is the right way to do this?
If you are asking what I think you are:
“Can I use part of a paid asset in my own, free asset”
Then my response would be “Obviously not, feel free to recreate parts of the paid asset but by no means should you redistribute it freely.”