I think applying programming in GIS is the most important skill to have. I especially enjoy applying python and it helped in my previous job and the current one. I advise everyone to learn at least the basics of programming and try some simple scripts.
Hello, I recommend this as a starting point (from 2009) www.esri.com/arcgis-blog/products/arcgis-desktop/water/gis-hydraulic-modeling/ and this as a tech follow-up using Esri tools: solutions.arcgis.com/water/help/sewer-utility-network-foundation/design-pattern/what-is-the-data-model.htm
I have some of the things that you have showed about GIS. I appreciate it. And I have also made one video about the basic concept of GIS. Hope you check it how it is and can give it a review. 😊 #NeetuD