The template is equivalent to creating both an ASP.NET Core project to act as an API backend, and a Vue Js project to act as a UI, but with the convenience of hosting both in a single app project that can be built and published as a single unit. There is no dependency of Node js. Just follow the existing example to extend the application.
Vue is a progressive framework for building user interfaces. Unlike other monolithic frameworks, Vue is designed from the ground up to be incrementally adoptable. The core library is focused on the view layer only, and is easy to pick up and integrate with other libraries or existing projects. On the other hand, Vue is also perfectly capable of powering sophisticated Single-Page Applications when used in combination with modern tooling and supporting libraries.
https://marketplace.visualstudio.com/items?itemName=TechQuantum.DeepakAspNetVueJs