Reading scholarly, peer-reviewed journal articles is a skill that you develop. Journal articles (particularly research articles) are organized in a way that facilitates a more selective reading process, i.e. skimming and/or reading sections in a different order.
There is no single way to correctly read a journal article. Ask your professors - they'll each have their own way of breaking down and reading articles, both within and outside of their field. Below are resources and guidelines to help you: