You can sort by actual file type in most search engines. Duckduckgo also has a specific ‘transparent’ option. I don’t know if that’s the case for others but they probably have it too.

This is what happens when you ask ai for an image with a transparent background

There’s pretty good free software and websites with ads for cutting out images these days. Should work perfectly with an image like that. It’s not as much of a pain as it used to be. On Linux I use defuse (io.github.shonebinu.defuse on flathub)

Absolutely brilliant and accurate

Or when searching the linked image is gone, and the cached image without transparency is your only choice.