Writing a good article is a science. Academic writing requires the use of formal style, the use of correct punctuation and the construction of paragraph. Your ideas in each paragraph must be united, coherent and must be supported by correct evidences. These techniques are too technical for a beginner, therefore, it's suggested to get an exercise writing book or watch instructional videos related to these topics.
For now, start your training by reading articles in blogs or in article directory. Simply read articles and observe its various styles: Is it written informatively? What perspective is used? Is it written in present or past tenses? It's also important to observe the choice of words that are used. Some articles are written with friendly vocabularies while others prefer to use heavy words. By performing the techniques above, you can verify if your observation is right or not