Urgent Diabetic Wound. He should take?

My dad Diabetic, has wound in his thumb foot. It happend bcz a clincher ( keel) in his slipper pinch his thumb. At first the wound was dry and had round hole And there is no bleeding. Later we cleaned up with Dettol and then put Medosprin powder. In a week the wound started healing but area around that wound getting white ,and while pressing that white area liquid comes out from that wound. There is a pain while pressing that wound. We see the doctor, He said to control sugar level. And we see another doctor today he said to see surgeon and not to use any Dettol to clean up and Medosprin powder. He has been taking medicines GLIMY M2 for long time And another doctor prescibed"Amaryl 1mg" along with glimy. My dad sugar level in fasting is 125 and after breakfast it spikes to 300. He is not on insulin.How to treat that wound ???i'm really worried. What type of doctor should we see?? Which food he should take ? He is taking Besan ki roti+Chana Daal in lunch dinner &breakfast Roti Egg MILK