Take a look at the low carb diet as a starting point - it would help you lose weight, reduce the need for insulin and stabilise your bg. You’d need to build up some knowledge on what food has carbs/fats/proteins (book and app Carbs & Cals are pretty useful for that) and what balance of those three you need to achieve best results, but it’s very much worth it. It takes everyone a bit of time to learn, adapt and experiment to see how this fits with your lifestyle, so don’t beat yourself up if it takes a few weeks to get into an optimum routine!
Other diet you might want to read about is the ketogenic one (I’m T1 as well and that’s the one I’m on at the moment), but it’s a bit more extreme and less flexible than the low carb diet so I’d recommend starting with the low carb one and see how that works for you.
I hope this helps.