I haven’t used Discord in a while so YMMV but I used to use WebCord and screen sharing worked pretty well IIRC. It uses an up-to-date Electron version which has better support for modern desktop Linux protocols. There are probably plenty of other alternative clients that just repackage the web app with better Linux support. There’s also gtkcord4 which is a native Gtk client, though definitely not as polished as the official client.
I have used Fedora for nearly all the time I’ve daily driven Linux, and haven’t encountered any problem that a newbie would encounter and couldn’t overcome, excluding distro-agnostic stuff. Yeah, the h264 shit sucks, but if you use flatpaks you shouldn’t have to worry about it. And if you ever have to face SELinux, then you’re probably doing something that’s beyond beginner level.