from xhtml to html5

Hi all, or hello world!
1)Is there a way to change this template: http://www.consulcesi.it/ in a new one in html5?
2)Is possible to keep the same structure of the Urls?

The more is similar the more is good ;)

Thanks!
Lorenzo

p.s.
this is my first post. Dunnow if is the right discussion but...any help for the questios before? :)