Citation styles vary but they all tend to include the same information. The key is to learn how to identify the different parts of the citation and then plug them into the correct place for the style.
Many scholarly journal articles are available online which can cause some confusion. Should you cite it as a journal article or as a web page? Journal articles and web pages have distinct characteristics. Both web pages and journal articles are often found by clicking a URL or link, but even when a journal article is accessed through web page, you would still cite it as a journal and not as a web page.