@changeling You can follow accounts on #PeerTube from Mastodon (or any other ActivityPub application). Just search for their handle and follow them _locally_, so to speak. Their videos will appear in your timeline, too, and you will be able to like them and comment. It's actually easier that way.

Here's are a couple of examples:

@chriswere,
@veronicaexplains

Try subscribing to them from here as you would with anybody else.