Ubuntu Server installation is pretty straightforward , then connect via ssh to server instance and install Gnome 45 desktop environment via command $ sudo apt install ubuntu-gnome-desktop. Reboot Ubuntu Server’s instance and log into newly installed Gnome 45 environment. Now you are ready to proceed with KVM setup on Ubuntu 23.10

Source: LXer – Install KVM on Ubuntu Server 23.10 (Gnome 45 Desktop)