how to create complete webpage to change differ languages

Well, you cannot.

However, there are technologies which help you do it. Please look into globalization, localization, thread.UICulture, etc, topics and you will know.

There are two many variables here. All web-pages are static or dynamic? Is any textual data coming from database?

If yes, you will probably need to use resource files. You will also need to store data in different languages in database.

There are two many things to look into.