Assuming you are a Linux beginner picking your first distro, I'd recommend something stable, established, and well-known. Especially since you are asking.

So Debian or Fedora. Maybe OpenSUSE, Mint (Debian/Ubuntu base), vanilla Arch or EndeavourOS (Arch base).

Wouldn't recommend up-and-coming perennial community derivatives depending on a very small number of volunteers like Omarchy to someone who does not yet have the confidence and experience to fork/maintain it themselves. Projects like Omarchy can be great as inspiration and starting point for your dotfiles once you have your bearings and can judge it yourself but not wise to treat it as a "black box" or set-and-forget the way you can more safely do with a classic distribution.

Then you can of course run either KDE (good choice), Hyprland or whatever other Desktop Environment and Window Manager you desire on your dist of choice.

Or try a few different ones and see what sticks for you.

I didn't like kde fedora. DNF is a headache. Haven't tried omarchy but I liked arch the last time I used it

In the grand tradition of those who have come before us, you should distro hop to all of them.