The following documentation was found that indicates that:
simply create a new docker (hosted) repository as documented in Repository Management
The problem is that the format docker seems not to be available when trying to configure a "Hosted repository"
Nexus 2 was deployed instead of Nexus 3. The docker feature seems to be introduced since Nexus 3.
This blog indicates how to configure a docker repository and how to push and pull docker images.
The blog contains multiple pictures. The following picture indicates how to enable the docker registry:
