Let me start by commiserating with you. Literary devices can be hard work to identify as you start getting used to them. However, there is hope. It does get easier. Let me give you a hint. Some of the easiest literary devices to identify are alliteration, which is when words have the same consonant sound at their beginning, and similes, which is a form of comparison (figurative language), identified because of the word "like" or "as" that is used to construct the comparison. Let me offer the following example of a simile:
She sat with her head thrown back upon the cushion of the chair, quite motionless, except when a sob came up into her throat and shook her, as a child who has cried itself to sleep continues to sob in its dreams.
Note the use of the word "as" in this quote to identify the simile comparing the way Mrs. Mallard is sitting and sobbing intermittently to a child sleeping. This of course makes us feel sorry for Mrs. Mallard as she copes with her grief, but also shows how she is overwhelmed by the force of her grief at moments, as the comparison makes us think of a child experiencing a bad dream and involuntarily sobbing as a result. I hope this example will help you find more literary devices. There are certainly plenty there!
One example of a literary device used in this story is irony. According to the doctor, Louise "has died of heart disease -- of the joy that kills." The doctor has assumed that Louise's heart could not withstand the excitement of learning that her husband was alive. However, Louise is grief-stricken to learn that he is alive because she has lost her freedom. This reveals how confined women often felt in society and in their marriages during this time period. The brief time Louise relishes her future opportunities is enough to make her lose her will to live. Her life ends when she discovers her husband is alive.