Wonder if someone could provide answers

The obvious thing in this story, is that your Dad's blood sugars are far too high. High blood sugars cause glucose to appear in the urine, which encourages infection by fungi.
Smelly breath is often ketones, which are not in themselves dangerous, but in conjunction with high blood glucose could be diabetic ketoacidosis [DKA] which may be a life threatening emergency.
First you need to get your Dad throught this crisis and then when it's over, help improve his blood glucose control. The doctors may well just suggest increasing his medication. The alternative is to decrease the foods which raise blood glucose [the carbs] to be sure things are going right, he needs to test blood glucose at least once per day. If your GP won't prescribe test strips, even after you remind him/her of the crisis, You may need to buy them. Successful improvement in control will make you Dad feel much better and reduce the risk of a repeat of this event. After that stage a lot will depend on your Dad's motivation. If he wants to be well and will discipline himself to modifying diet and testing, he'll succeed. If he's one of the many patients who don't want to be better, he won't be.
Hana

Hi Smigger25. I'm wonder whether the kidney infection was partially the result of high blood sugar rather than the cause; it may be just the symptom. I might challenge that the weight increase from 13 to 19 stone was due to diabetes. No doubt your father will be insulin resistant, but the diabetes is more likely to be the result of the weight increase not the cause. I would suspect that your father's diet isn't ideal. Hopefully with some gentle guidance from you he can reduce his weight thru a low-carb diet and the right portion sizes until he reaches a satisfactory BMI and the insulin resistance fades. His sugars should reduce unless his pancreas is failing in which case he will need the appropriate diabetes meds.

Hi. Let's hope your father gets the right diagnosis and treatment so he can recover. It's possible the hospital may give him insulin short-term which should help and won't be needed longer-term. There are so many diet books and I'm afraid I'm not personally aware of the best ones. This forum at large has some good dietary advice. In summary, keep portion sizes down if you can, avoid too much snacking, keep carbs, say, below 150 gm/day to start with and have low-GI carbs to smooth sugars this means wholegrain bread, wholemeal flour, pasta and so on when your father does have them. Have plenty of veg and the less sugary fruit. Protein is fine and even fat in sensible quantities; unsaturated when you can such as fish. Avoid sugary drinks including fruit juices. It's worth studying the labels of food in the shops; it can be an eye opener. Low-fat fruit yoghurt is loaded with sugar, for example, but there are a couple brands with no added sugar if you search the shelves. So, it can be hard work but there is a way thru. I wish your father well.