Hi @spiderman90 , 

I believe that Esri data loading tools is the easiest way for you to start. You can find it here: https://solutions.arcgis.com/shared/help/data-loading/

You can also find a lab on how to work with dlttools that can help you get started. It is available here: https://learn.arcgis.com/en/projects/load-data-into-the-arcgis-utility-network/

However, keep in mind that implementing UN, especially for production scenarios, is not a trivial migration. Depending on the organization's needs, the organization's expected business outcomes, the quality of your organization's existing data, its existing data models, and some other factors, migration can vary from medium to big effort. If you have a chance to evaluate consultancy support for this initial implementation, I'd recommend trying it.

Best