Visual Studio 2017 Reference Manager is empty

Targeting .NETStandard 1.4

That is not ".net classic", you picked a new project template that is available since VS2017. .NETStandard is pretty similar to PCL of old, it helps you create a portable class library that is usable on multiple platforms. An improvement over PCL, you no longer have to select which specific platforms you want to support. Being "standard", all framework assemblies you could pick are already included, that's why the list is empty. PCL worked the same way.

Beware that there are a lot of Class Library project templates around and choosing the wrong one is easy to do. You'll have to pick the one named "Class Library (.NET Framework)", that's the one that targets the classic desktop version and gives you a non-empty list to choose from.

I overlooked this being a .NET Framework targeted project rather than a .NET CORE

Please see below assembly location.