There is no restriction for installing ArcGIS Desktop on the same machine where ArcGIS Enterprise has been implemented. Just ensure that your machine meets the optimum system requirements and you should be good to go.
You can install ArcGIS Desktop 10.5 in the same machine where ArcGIS Enterprise 10.5 is also installed. Ensure the versions are same for all ArcGIS products installed in the same machine.
There is no restriction for installing ArcGIS Desktop on the same machine where ArcGIS Enterprise has been implemented. Just ensure that your machine meets the optimum system requirements and you should be good to go.
