I have T2 diabetes, @Jimboy - I was diagnosed about 18 months ago.
I will have fish and chips occasionally - less than once a month - and I only eat a few of the chips.
I use a dexcom continuous glucose monitor, which alarms if my blood sugar goes too high or too low, and I’ve never triggered the high alarms after fish and (a few) chips.
When I was diagnosed, I overhauled my diet - if I have rice or pasta, it is brown rice/wholewheat pasta, and I have small portions. I almost never have bread - I used to have a sandwich for lunch every day, but now I have cold chicken, coleslaw and beetroot, or hummus with raw cauliflower and carrot, or low carb wraps (from the Mission brand) with sandwich filler or grated cheese and coleslaw.
I am eating more fruit than I used to, but I monitor my sugars to make sure the sugar in fruit doesn’t affect me. If I have potato with a meal, I have a very small portions, and fill up the plate with veg or salad.
One thing I have been told - if you cook and chill rice or baked potatoes, then reheat from chilled or from frozen, this changes the carbs, so they don’t spike your blood sugar.
If you go to Dexcom and Freestyle Libre, they will each send you a continuous glucose monitor to try - the dexcom lasts 10 days and I think the Freestyle works for 14 days - so you can experiment and see what effect different foods have on your blood sugar - my SIL is T2 too and she can’t eat tomatoes - they spike her blood sugar badly - but I can eat them with no ill effects.
I was advised to avoid low fat products as they often hide sugar in them - the sugar helps make up for the loss of flavour from reducing the fat. I often have Greek yoghurt with fruit for pudding, and I get the 5% Fage.