Because there's so many new fedizens I will share this site for finding communities that are on lemmy and kbin.

The site: https://lemmyverse.net/communities

To see kbin "magazines" (that's how subreddits/communities are called on kbin) you have to switch to displaying them in top right corner:

Or you can just open this link: https://lemmyverse.net/kbin/magazines?order=followers

And to go back to displaying lemmy communities you have to press on "communities" in the middle on the top of the site: