Look diet depends on, history of CKD, what medications your dad is taking and also dialysis procedure of any. For normal
kidney patient who is not on dialysis very low protein diet is prescribed.
Electrolytes are to be avoided. Water input must be monitored based on out put. Some fruits like watermelon, grapes, mangoes etc are to be avoided. For a complete dietary guidance you can take appointment. If at all seeking appointment message personally.