Read the LabVIEW Help. https://www.ni.com/docs/en-US/bundle/labview/page/front-panel-controls-and-indicators.html
Both provide a list of values, but enums are their own datatype whereas rings are integers. Enums are not usually used on the front panel of top-level user interface VIs since they don't look like "natural" dropdown controls. It's not unusual to find enums as front panel controls of subVIs especially if you want to provide a restricted set of values. Enums are self-documenting - if you connect an enum to a case structure then the case elements will have the same names as the enumerations.
