I don't know your primary language. Are you conversant in English? If so articles in German are used, for the most part, as they are in English with one very important difference, they are gender specific. You'll learn about that as you get further into your lessons. Also sometimes in German, an article is not used at all whereas it would be in English, for example when referring to a profession. In English we would say he is "a" doctor. In German the article would be omitted, Er ist Artz.
Hope this helps a little, but you'll just have to get further into your lessons before it becomes clear.