Seriously, you need to take control and do as much research as you can yourself. Please don't rely on the GP for advice re diabetes. They generally don't know enough about it to offer any worthwhile advice. Likewise, some of the "specialist" diabetes websites are absolutely crap for realistic advice.
I've been T2 diabetic for 25 years and had been pre-diabetic for 5 years before that. All I've ever had from GPs (and their so-called "specialist" diabetic nurses) is the generic advice from the poor NHS leaflets, i.e. the ridiculous "cut down eating mangoes" and eat more berries, kind of thing. Yes, technically correct, but not particularly helpful. I've also twice seen NHS dieticians who have likewise been useless for any realistic advice. GPs just constantly put you on more drugs and higher doses - it's a very easy answer for them as it doesn't require them to spend any time thinking/advising you - much easier to give you a new prescription with another drug on it! As years have gone by, my HAB1C has just increased, and every few years, a higher dose or a new drug added into the mix has been their answer. Even saying that, for the past five years, my HBA1C has been increasing above the target range for diabetics and the GPs didn't even pick it up, I just kept getting "satisfactory, patient can be advised" texts after the annual blood test. That's despite me mentioning at the annual check up that my finger prick tests were nearly always far too high only to be fobbed off with the diabetic nurse saying the GP would flag it up if HBA1C was too high (they didn't).
This Summer, I took control after starting to get finger prick results of 20+! As usual, the HBA1C was marked by the GP as "satisfactory", but I was having none of it and insisted on a GP appointment. I saw a different GP, a locum, who was visibly aghast at the screen of my HBA1C results and immediately wanted to put me straight onto insulin. I asked for alternatives, and he said about the Libre continual monitoring system which may help "IF" I was serious about changing diet and food and that I could have a free 2 week trial. I jumped at the chance. It's an absolute revelation, to be able to see the blood glucose levels rise and fall within an hour or so of eating, exercise, taking the medication, etc. In just two weeks, I made massive changes, just changing the time I took the drugs helped, and I discovered which foods "spiked" my sugars and which kept them higher for longer, and of course, which didn't move them at all. Also, saw the importance of portion size - i.e. 2 or 3 small/new potatoes didn't nudge the blood sugars at all, nor did a small slice of brown bread, so I learned I could eat things that were supposedly "bad" in moderation rather than cutting them out completely. After 2 weeks, I had a follow up phone consultation with the practice diabetic nurse, who could see the results live on her screen as it was linked, and she couldn't believe the difference, my daily average blood sugars was falling day by day, the daily patterns were smoothing out rather than being a mountain range. Don't know how she justified it, but she's put me on regular repeat prescription for it so I don't have to buy them myself (needs replacing every 2 weeks), despite T2 diabetics not being eligible under the NHS!
I've now been on it for a couple of months and my blood sugars on average are well within "normal" levels, the system shows an estimated HBA1C of "normal" levels. None of that is with strict dieting, mostly just learning what foods "trigger" high blood glucose in my body, and reducing them through smaller portions of the "bad" stuff made up with larger portions of the "good" stuff - for me that is, there are foods on the "naughty" list which don't spike my sugars at all, and some things that I should be able to eat as recommended for diabetics that do increase my sugars. It's a lot more complicated than "bread is bad, berries are good". I've also looked at quite a few facebook pages and other social media posts on diabetic lifestyles and learned a lot from them too.
I think what I'm saying is that the NHS, generally, is crap for diabetic and weight loss advice. There's lots of advice out there, so you really need to do your own research. And more than anything, get yourself a free trial of the Libre monitoring system - even just 2 weeks will really help you if you're seriously about wanting to solve the problem without a cocktail of drugs. I've also lost a stone in weight over the couple of months, not by doing much more exercise (I walk daily anyway), but by pretty modest changes to what I eat!