Your father is having diabetic Nephropathy
and as such he has to be put on dialysis
as there is no medicine which can reduce his creatine
,urea and potassium.
Although he is normal at the moment but this is temporary .
However dialysis is just a temporary treatment,as renal transplant is the final answer.
You must consult a nephrologist
and seek the management plan as the treatment will depend upon his physical condition.
Without the renal transplant,prognosis is not good.