Creatinine level is 1.27. Gfr 57, A1c 5.7... Md said drink more liquids...I think the numbers suggest greater problems. Thoughts?

Yes. You are right. Your GFR is abnormal and should be worked up. Your history suggest HTN which can cause Chronic kidney disease. Drink to thirst, don't drink excessive fluids. Also need an ultrasound to ensure no back pressure to the kidney given your BPH. A Urine test, Up/Uc ratio may be needed. Please seek care with a kidney doctor.
No, drink liquids. If the creatinine is high just recently, this is usually dehydration and you need liquids. Your hgba1c is a measure of your diabetes and shows excellent control. The GFR is calculated from the creatinine so it's the same thing. Increase you water intake first. If the creatinine remains high, then you need further investigation. The doctor probably got a urinalysis as well.