Actually, insulin can be conducive to building muscle, so much so that’s it’s often used by steroid abusers as part of a cycle.
Building muscle is hard work though, you need to run a large calorific excess, I typically have to eat an extra 1,000-2,000 calories a day if I want to gain muscle, which of course can cause issues with BG control.
Exercise wise, I found a 5X5 programme or a “starting strength” programme most useful, simple heavy, low rep caveman exercise like deadlifts, squats. If you have a google on the above terms you’ll be able to download a programme.
You’ll need to ensure you rest and refuel yourself correctly during recovery, doing this if you are low carbing is extra tricky, I could not avoid a hypo five hours later following a squat session unless i’d had 200g of carbs
Stretching is also very important as if your do these programmes as intended you’ll get a lot of muscle soreness during recovery.
Progressive overload is also key, your body will adapt quickly, so every few weeks the weights must get heavier.
Might be useful to get a personal trainer to guide you through the programme for first couple of weeks, or perhaps find a lifting buddy?
I’ve gone the other way now, keen to be as lean and light as possible the older I get ha!