# Prepare folder for images

mkdir ~/.qemu_imgs

# Creating hard disk

qemu-img create -f qcow2 ~/.qemu_imgs/image_file.cow 4G

# Install operating system

qemu-system-x86_64 -cdrom ~/Download/image.iso -boot order=d -drive file=/home/<user>/.qemu_imgs/image_file.cow,format=qcow2

tips: Get the mouse after grabbed by qemu: Ctrl+Alt+g