want to switch from html,css to asp.net.(1 year exp in html)

I agree it is possible, also 1 year in HTML is a really nice thing but the question is exactly what experience was that.

Nevertheless I would recommend you to try out these HTML, CSS and JS programming tests just to see if you need some further polishing or practising in that area.

After you have covered that holy trinity of a web development you can start with ASP.NET, but I wouldn't use that Sibeesh's codeproject link. That is a WebAPI part which is not something that you should focus at first.

If I were you I would focus purely on ASP.NET MVC, and again when you feel you are ready you can use this site with various programming tests to estimate your knowledge.