The main browser to use WebKit these days is Safari. You’ll find that on macOS, iOS, and iPadOS. I’m guessing that would be why someone downvoted me (some people have strong feelings about Apple, even though WebKit is Open Source and is very highly privacy focussed).

I had thought there were more options out there outside the Apple ecosystem, but it seems many of the browsers I once knew were using WebKit moved at some point to Blink (like Maxthon and Slepnir). The Gnome Epiphany browser for Linux however is built atop WebKit.

There are others, but you’re not likely (or able) to use them on desktop systems. PlayStation’s Orbis OS for the PS4 and PS5 uses WebKit as its underlying browser engine, for example. And there is WPE that is intended for use in embedded system environments (like for digital signage).

I did think there were more options out there (there once was!), but it seems a bunch of them moved to Blink when I wasn’t looking!