Fedora or Ubuntu. No need to overthink it. They are the two biggest distros in popularity by far (except Arch, which probably beats Fedora), so you have access to maximum mindshare and previous troubleshooting.

Including Arch, these three distros are among the most polished, stable, and well-documented. Arch takes quite a bit more effort, so a beginner without much time on their hands should start with Ubuntu or Fedora.