Do we need to push _includes and other directories which now with minima as a default theme are not created in site's folder if site is hosted on github pages?

To start with I am new to Jekyll.

I am not able to get the Disqus comments section added to my blog. I was wondering could the reason be that we need to push the directors that created in gem path of minima?

Yeah, we need to create the folders that are overridden and edit the relevant files in those folders, disqus_comments.html for my case and push it to GitHub if you are using Github pages.