How to migrate - free content?

I am trying to migrate some assets from the Free Vehicle Game.
But for some reason, I am getting the message that the content can’t be copied.

Is it not possible to migrate and copy assets from free projects?

yes content cant be copy and paste. u can migrate easily. do select mesh in viewport and press ctrl + b that will select asset u want to migrate in content brower. now right click go to assets and migrate to the content folder of your project. let me know that serve your purpose or not.