Visualizing Military Symbology data on a map requires two steps:

// Create the coordinate reference in which the model will be defined.
auto crs = TestCrs::epsg4326();
// Create an APP-6 symbol "unmanned aerial vehicle unit" and set a value for its text modifier "Unique Designation".
auto symbol = MilitarySymbol::create(MilitarySymbology::Standard::App6d, "10060100001103000000");
symbol->putValue(MilitarySymbol::Modifier::UniqueDesignation, "Regular");
// Copy the symbol to a Feature instance and a point geometry.
Feature emptyFeature = Feature::newBuilder().dataType(MilitaryDataModel::getSymbolType()).build();
auto featureGeometry = GeometryFactory::createPoint(crs, 0, 27, 46);
auto feature = symbol->copyToFeature(emptyFeature, featureGeometry);
// Declare the model metadata.
auto modelMetadata = ModelMetadata::newBuilder().title("My Symbology Model").build();
auto featureModelMetadata = FeatureModelMetadata::newBuilder().dataModel(MilitaryDataModel::get()).reference(crs).build();
auto modelBounds = GeometryFactory::createBounds(crs, featureGeometry->getLocation(), 0, 0, 0);
// Build an IFeatureModel containing only the feature we just created.
auto militarySymbologyModel = FeatureModelBuilder::newBuilder()
.modelMetadata(modelMetadata)
.featureModelMetadata(featureModelMetadata)
.bounds(modelBounds)
.features({feature})
.build();
// Finally, put the model in a layer, and add it to the map.
// A default IFeaturePainter is automatically deduced from the model's data model.
auto layer = FeatureLayer::newBuilder().model(militarySymbologyModel).build();
map->getLayerList()->add(layer);

See this article if you want to customize the styling of your military symbols.