That depends on the backend storage type. If you use iSCSI, there is no problem installing the clusterware and everything is as it would be on real hardware. If you don’t have iSCSI, the easiest method is to run a additional iSCSI portal as backend storage for your cluster.
Keep in mind that PVE or more precisely KVM is not a supported environment for Oracle software (as is VMware and everything besides Oracle VM). If you run into a problem, Oracle support can say that you’re running in an unsupported configuration and that you replicate your problem on hardware. I’ve never seen this, but it is a noteworthy potential risk. Licensing can also be a problem (or just darn expensive), please consolidate with the Oracle LMS before running into licensing issues.