I guess it's depending what are you are writing about - Usually the introduction is basically what are going to talk about - For example: If you going to write about 'Dogs or cats' and you say dogs are better, the introduction needs to say why dogs are better and the rest of the paragraphs is proving why dogs are better - Hope this helps! Sorry if this is not what you were looking for :/
You include a sentence that grabs the readers' attention, then give some general info about your topic. Make sure that it's at least 5 sentences and then make a good outro.
