Read the "Getting Started" page of the OpenSilver documentation for a step-by-step tutorial. Basically, you should download the .VSIX file (the extension for Microsoft Visual Studio) which installs the Project Templates: The .VSIX for OpenSilver can be downloaded from: https://opensilver.net/download.aspx (Free, Open Source, MIT Licensed) The .VSIX for CSHTML5 can be downloaded from: http://cshtml