I’m currently reading a book (Robbin Hobb, Farseer trilogy pt. 2) that deals with this.

I really like how it describes animal thought & communication:

The author translates very reasonable impulses and non-language thoughts for a dog/wolf to have into prose that the hero of the book can relate and respond to. Yes, they have a telepathic connection; that’s the fantasy part.

It’s not precise of course, but I find it pretty reasonable from a scientific pov while still fit for a fantasy novel.

Basically, the above exapmple and I agree with the currently top comment by @e0qdk@reddthat.com.