Answer: The symptoms seem to line up with Cataracts which is an worsening degeneration of the lens of the eye. Treatments and recommendations vary depending on the extent and area of the cataract, but often include surgical correction (such as a lens replacement), regular eye exams, pharmacological treatments (such as dilation eye drops), and more. To help better understand and answer your question to the depth needed depending your class and teacher, I suggest you research "Cataract Nursing Care Management" for a more in-depth Study Guide on the topic.
I hope this helps! Let me know how it goes! :)
P.S. Those yellow halos (specific type of visual change) are often also used as a hallmark sign of Digitoxin toxicity (type of medication often given to heart failure patients). This question, however, does not give the patient's medications and also context clues including the white cast over the eyes and gradual vision loss point towards a degenerative eye problem (such as cataracts).