This is where you might note what the points the author has made might mean in a larger context. You might also consider why your instructor has asked you to read this article. Perhaps the author advanced thinking in the discipline. This, along with the work in the other steps, is the basis for a critical evaluation of the article. Even if you don't know anything about the topic, you can make some judgements about the article and how well the author made her or his case.
Evaluation is a bit harder.
If you are not familiar with those other articles, it can be hard to evaluate well. However, you can do a fairly good job of it by considering the conventions of other, similar articles. Your comments might be one or two words, or might be longer. Remember, too, that these notes will allow you to quickly review the article later on. You might do well to write your future self fairly detailed notes.