I have recently been trying to learn TypeScript, and in some of the videos I have been watching after installing the \'Web Essentials\' extension when working with a .ts fil
In Visual Studio 2017, you need to install the "Node.js development" Workload during the installation process or modify your existing install in the New Project dialog by clicking the "Not finding what you're looking for? Open Visual Studio Installer" link.
Then File > New > Project... will include Javascript and Typescript project templates under the Installed category.