You're being unfairly downvoted, so allow me to actually answer your first question.
QEMU doesn't have much of a GUI to speak of. It's a virtualization framework with some CLI tooling on top of it. Frontends/management UI's/etc are left as an exercise to the community so you can find one that suits your needs.
A recent Windows build used GTK3 decorations; I was very surprised to see that appear. You are right that it is quite low on functionality, its menu allows powering off and rebooting the VM, and gives access to the serial console as well as a command-line interface for the emulator.
QEMU doesn't have much of a GUI to speak of. It's a virtualization framework with some CLI tooling on top of it. Frontends/management UI's/etc are left as an exercise to the community so you can find one that suits your needs.
For example, a popular one for macOS these days is UTM: https://mac.getutm.app
QtEmu is another: https://qtemu.org