Creating a page on Wikipedia is not easy, specially if you are doing it for a backlink for your website. Actually you can create a page on Wikipedia but it will be deleted by moderators if it does not meet the guidelines. However, if you want a backlink, it is possible.
Wikipedia is one of the largest website, so it has an article on almost any topic. And your website must be covering a topic related to Wikipedia article.
There are two ways to add your website link to Wikipedia. Any good article on it has two sections at the bottom of the article; References and External Links.
An article on Wikipedia is about Indian bookmarking websites, so if you have a website about Indian bookmarking you can add your bookmarking site in external links section. This is just an example; you can study many more examples.