Comments are controled at your blog page in Comments Tab. You can choose from three options: Kirby Commentions, Embed third party comments, and you can choose None if you don't want comments on your website.
This options is pretty straightforward, just add embed comments code your get from Disqus or your prefered provider, and add them to the code-area. In Site Settings Labels Tab you can customize comments header text.
When you enable Kirby Commentions, comments from all articles will be listed in blog Comments Tab. Both Pending and Approved.
Every new comment will have to be aproved by Admin to be visible on the frontend. You can change that setup if you want https://github.com/sebastiangreger/kirby3-commentions#default-status
Also, on every article you can see comments specific for that article. Below the article
Kirby 3 Commentions is fantastic plugin, and really complete solution with large amount of options. By default we selected options that most users will find just right, but if you want something different in setup most of the things can be done by changing options in
site/config/config.php. You can check all available options at https://github.com/sebastiangreger/kirby3-commentions#config-options
Commentions by default support English and German language. For translating to more languages check out this section https://github.com/sebastiangreger/kirby3-commentions#translations.
You can extend it farther by adding some inbuilt hooks (like email notifications), you can check them out at https://github.com/sebastiangreger/kirby3-commentions#hooks
For enabling the Webmentions proceede to the next section.