How to copy static file to build folder

I want to copy CNAME file inside the docs folder. Is there any way when I run bundle exec jekyll build -d docs can I copy CNAME file also inside the docs folder treating as a asset or static resource file please help?

what is the actual name of the CNAME file? CNAME? static files should copy over no problem unless they start with a period or underscore or ~? if it is one of those then you need to list it in your config file under include.

is the cname file in the same root as the rest of the site?