Well I'll recommend you reading some ASP.NET MVC book instead. Because it will give you basic understanding of MVC concept. But still:
You can't use webforms in MVC. Because it's completely different approach;
MVC gives you more flexibility over markup, you can customize your application easily. Again read about MVC pattern. Webforms instead are faster to develop, but heavier in terms of size and have some ugly things like viewstate;
Yes, you can. But in different pages, not in the same page.