Have you tried ML.NET?
It's a new machine learning framework made specifically for .NET developers.

Download .NET Framework 3.5 SP1

Not sure what to download? See recommended downloads for the latest version of .NET.

Runtime

The runtime includes everything you need to run existing apps/programs built with .NET Framework.

Download .NET Framework 3.5 SP1 Runtime

If you're using Windows 10, Windows Server 2016, or Windows Server 2019 we recommend installing .NET Framework 3.5 through the control panel.