How to CREATE A NEW ARTICLE in wikipedia? on the main page there is no such link like "create a page" or such?

This is a question that comes up a lot, though in slightly different forms. The reason you don't see a "create a page" link is that they want to discourage page creation by new users. Wikipedia has had a lot of PR fiascos, and usually established users are to blame. Yet, they come down hard on the newbies. To make new pages in the English language Wikipedia, you must first have an account (the "log in/create account" link should be in the upper right corner of the page). Some of the Wikipedias for the less used languages, like Volapuk, let you create articles without being logged in. Next, you need to show that the topic is "notable" (whatever that means to whoever's in power right now) and provide citations from academic journals, newspapers and books. It doesn't hurt to have good spelling and grammar, so I would recommend writing up a first draft and putting it through a spell-checker. When you have those things ready, log in to Wikipedia and use the search box to look for your topic. If there's no article, you'll be given a red link which you can then click on to create the article. You don't have to preview in Wikipedia, but you should just to make sure it looks the way you want it to. Once it looks good to you, click the Save button. But even after all that work, there's no guarantee your article won't get deleted with no explanation besides a few cryptic acronyms. So, if you really want to create a new article in Wikipedia, don't put as much effort into it as you would writing an article for which you'd be the only author, or have just a single co-author. Just make sure to cover two or three important facts, back them up with references, and spell-check everything before you save. If that gets deleted, it'll be annoying, but not as much as if they deleted something you worked very hard to put together.