Double-click on the executable file downloaded for Visual Studio 2017 version 15.3 in the earlier section. This will start the installation. C# comes by default in every Visual Studio installation, so there is nothing to do for C#. Visual Studio 2017 also comes with F# support in all its editions: Community, Professional, and Enterprise. F# is an optional component though. The installer includes it as a selectable workload, or you can select it manually in the Individual components tab, under the Development activities category. Select F# language support:
Visual Studio 2017 version 15.3 comes with ...