Do I need Oracle Virtual Box to run the emulator?

No. On Windows, Genymotion Desktop uses VirtualBox as the default and recommended hypervisor, but on macOS it now recommends QEMU instead, and on cloud products no local VirtualBox is needed. If you’re on Mac M series, VirtualBox is not available, and if you’re using Genymotion PaaS or SaaS, the virtual devices run directly in the cloud. See Genymotion and macOS - An error has occurred while trying to create a virtualbox host-only network interface.