Grade 2 fatty liver is alright, don't worry much about it.  It can be managed my regular check ups with blood investigations. Some of the changes that you can do are- reduction of weight if your father has high BMI, no alcohol consumption if he drinks, have high protein diet and low carbs. If he is diabetic, then it needs further evaluation and medicinal help. Can try Vitamin E too after consultation Regarding enlarged prostate with significant post void residual urine, Your father needs Urologist consultation. Basically he is unable to empty his bladder completely because of enlarged prostate. This needs some attention as urine stasis in bladder can cause urinary tract infections.

Need detailed history and evaluation for better treatment