Using Visual Studio 2019, I believe I have encountered a new bug. When I have an existing solution, full of various .NET projects of various types, adding a new Telerik Core Project does not actually create a Telerik project.
To be specific, using the menu Extensions/Telerik/Kendo UI for ASP.NET Core/Create menu item results in the "standard" visual studio template being used. Absolutely zero Kendo/Telerik logic gets added to the resulting project. If I use the new "magic search box", located in middle of top of VS 2019 window, and enter "add new telerik core mvc" the resulting listed items actually take you to the correct launch point. That is to say the resulting project does actually contain the needed references.
While both avenues result in a newly added project to your solution, the second option appears to be the only avenue to using the pre-defined Telerik Template.
In fairness to Telerik this might actually be a Visual Studio bug.