While I don't think there is a way to fully do this you can take a few measures to stop almost everyone from viewing the HTML.
You can first of all try and stop the inspect menu by doing the following:
I would also suggest using the method that Jonas gave of using his javascript and putting what you don't want people to see in a div with id="element-to-hide" and his given js script to furthermore stop people from inspecting.
I'm pretty sure that it's quite hard to get past that. But then someone can just type view-source:www.exapmle.com and that will show them the source. So you will then probably want to encrypt the HTML(I would advise using a website that gives you an extended security option). There are plenty of good websites that do this for free (eg:http://www.smartgb.com/free_encrypthtml.php) and use extended security which you can't usually unencrypt through HTML un encryptors.
This will basically encrypt your HTML so if you view the source using the method I showed above you will just get encrypted HTML(that is also extremely difficult to unencrypt if you used the extended security option). But you can view the unencrypted HTML through inspecting but we have already blocked that(to a very reasonable extent)