Authenticating AGOL For Use In QGIS - Part 1

I often work in a hybrid GIS environment, using both QGIS and ArcGIS/ESRI suite of software. Most of the time, I use ArcGIS Pro which connects seamlessly to my ArcGIS Online (AGOL) content. However, there are times when I need to connect to my AGOL content from a QGIS desktop environment. It's easy to connect to a public ArcGIS REST server, but what if you want to connect to a private one? There…