The toolset is written in C# and requires the .NET Framework to run. However, this only applies to the toolset itself. The installation packages you create with the toolset do not require any extra framework or software to be installed on the target computer. Similarly, there might be a few additional utilities required for some special applications (merge modules, patches) but only on your build computer, the client will only need the finished and self-contained installer package, nothing else.
If you don't have a design already in place and think templates are too limited, consider Adobe Muse CC. This unique little program concentrates on letting you design. Templates are handy, embeddable web fonts are great, and the sitemap view may be the best way to get an overall feel for what your site will have. Export it to HTML and you're ready for upload. It's part of the Creative Cloud bundle and also available individually for $14.99 a month with a yearly plan.
Your website needs a place to live on the web, and the quickest way to reserve your web address is to find a web host. There are a variety of cheap web hosting providers, and each one has a specialty. Look for a web host that offers a price that fits your budget, has the web tools you need to create your envisioned website, and provides support when you need help or have problems.