Fun fact: Jellyfin runs natively on Windows. Combined with something like Cloudflare Tunnel it's probably the easiest way to host a media server without needing to be a Linux admin.
I'd prefer using Tailscale so that I can also access it in their native apps on Android and Android TV.
Yes Cloudflare Tunnel can work with Jellyfin apps, but: 1) this exposed your Jellyfin to the world, and you are one vulnerable away to get owned, and 2) like other sibling posts mentioned, this is against their ToS to host streaming service on free plan on their platform.