I'm a little unclear on how the furry identity works. Is it like an LGBT+ thing where you just are this thing regardless of your feelings or desires, or does wanting to be a furry make you one? Like, I've fought against being trans much of my life, but now I see I pretty much always was. But I don't know if liking the puppygirl idea makes me a furry, or if that's something I have to have always been? (this is not a reaction to a recently popular puppygirl, I've meant to ask this for a while) I also may be terribly misunderstanding furries; that's a taboo subject where I live, so I don't know much.
Long-time furry here. Let me try to break it down a bit.
"Furry" at its core is simply an interest in anthropomorphic animals. That covers a wide spectrum of people ranging from those that only have an interest in the art to therians who identify integrally as nonhuman. Whether you are a furry or not is just a matter of self-identification and whether you choose to engage with the fandom. I know incredible artists with whole-ass fursonas that don't call themselves furries and that's totally fine.
The puppygirl idea is something worth exploration though. Being into that doesn't necessarily mean you are a furry. There's an entire subculture of pup play that exists and while there is a fair bit of overlap between that and furry, it is a separate, distinct thing. Just food for thought!
I've been in the fandom for almost 20 years and this is spot on.