This question already has an answer here:
I have created a Debian virtual machine in virt-manager/KVM/QEMU.
When I run the Debian virtual machine, I don't really need the desktop environment, which is also resource consuming. Can I start Debian only on a text virtual console (e.g. like ctrl-alt-f1) instead of the graphical virtual console (i.e. ctrl-alt-f7) on the virtual machine?