No, Mendix does not have specific built-in CMS capabilities.
You could built some CMS functionality with Mendix, but I would not recomend that in most use cases.
Mendix is for dynamic web applications while a CMS usually serves mostly static content.
No, Mendix does not offer a build in CMS. However, Mendix gives you to the tools to create your own CMS with the functionalities you want.