Qubes OS
Qubes OS is a free and open-source, security-oriented operating system for single-user desktop computing. Qubes OS leverages Xen-based virtualization to allow for the creation and management of isolated compartments called qubes.
VS
Nobara Project
Nobara Project is a modified version of Fedora Linux with user-friendly fixes added to it. The distribution comes with certain features that do not ship with the regular Fedora, such as WINE dependencies, OBS Studio, 3rd party codec packages for GStreamer, NVIDIA drivers, and some package fixes.