How does one interact with Mastodon with kbin?

On the kbin.pub. It said:

It can communicate with many other ActivityPub services, including Mastodon, Lemmy, Pleroma, Peertube.

I thought Mastodon (and maybe other federative platforms) are very different from kbin, in terms of the intended uses and functionalities. How do I interact with it?

When I make a thread on /m/kbin, what does it do on Mastodon?