The first one I saw was Debian 3.1 (Sarge). I was in school and our objective this time was installing debian + getting a working Xorg session. Never heard of Linux before, didn't get a working Xorg session, but wow man, there's something other than Windows and MacOS. I couldn't have imagined.
The first one I actually used on a desktop (laptop for school, in that case) was Ubuntu 6.06 (Dapper Drake).
I've tried oh so many different linux distributions over the years, I probably forgot most of them. Maybe some don't even exist anymore. My goal was always Arch Linux, having seen it on a schoolmates laptop. I really fell for the "here's a pretty minimum base, do whatever" thing.
In the end, I exclusively used Arch from 2020 until this year. Actually using Arch and reading the ArchWiki were probably what taught me most of what I know about linux in general and how things work.
I've been searching for a less DIY-solution which is still up-to-date (especially with kernels and mesa) and I landed on Fedora Workstation, which is what I'm currently using on my work latpop and desktop at home. I do miss some things from Arch, but Fedora has been pretty good to me and I, for the meantime, intend to stay here.
Yes it is. Though after using arch for a few years, I miss the abundance of packages.
If a package wasn't in the official arch repos, it was probably in the AUR. If you use arch, you don't need other package managers like homebrew on linux.