Hi and welcome.
Yes the dried fruit in a hot cross bun is part of the problem and there will likely be added sugar as well to make the dough sweet but the flour the bun is made with is probably a bigger issue.... same with any bread or bun/roll/bap, cake or biscuit. Diabetes is not just about sugar but all carbohydrates which are broken down into glucose by the digestive system and absorbed into the blood. Calling it "blood sugar" makes people assume sugar is the problem but glucose is the building block of all carbohydrates be they from grains like wheat or rice or oats.... or potatoes or fruit.... they all get broken down and become glucose and it is our high blood glucose (BG)levels which make us diabetic. Reducing the amount of all carbohydrates we eat (bread, pasta, rice, potatoes, breakfast cereals and fruit) will help to bring our BG levels down.
There are carbohydrates in almost all foods to some extent or other.... even lettuce.... but you would need to eat a ton of lettuce to have any real impact on your BG levels because it contains very little..... so the key is to understand which foods are highest in carbs and restrict those and eat more of the ones that are lower in carbs to fill you up. Of course none of us what to eat a ton of lettuce everyday as that is pretty unappealing, but there are plenty of tasty low carb foods to have with your salad or cabbage or cauliflower and don't be afraid to add a dollop of butter or a dash of a nice oil to your veggies.
Not sure where you stand on eggs but they are a versatile low carb food. I love omelettes with a variety of fillings and a big side salad with a large dollop of coleslaw. Cauliflower is wonderful stuff. It can be boiled and mashed to replace potato (with the addition of a good dollop of cream cheese and some wholegrain mustard) and you can have plenty of cheese on top as that is low carb. Cauli can also be grated and used as a rice or couscous replacement (takes a lot less cooking) or cut into steaks and roasted. Celeriac makes pretty good low carb chips or swede works OK too. Lentils, beans and peas are moderately carb rich but some people's bodies seem to be able to extract more carbs from them than they are supposed to contain. Sadly I am one of those people people whose BG levels spike quite badly with pulses, so I don't have them very often....
Breakfast can be tricky as it tends to traditionally be a carb rich meal (toast or cereals). Many of us have creamy Greek style natural yoghurt with a few berries and mixed seeds and perhaps a sprinkle of cinnamon or chopped nuts..... or eggs whichever way is our preference. There are special low carb recipes for muffins which don't use normal flour and can be used to make sweet or savoury "buns" to eat on the go or Nut bars can make a satisfying grab and Go breakfast.... Things like Nature Valley Protein bars are just under 10g carbs per bar so they can make a useful on the hoof breakfast. (The Salted Caramel and Choc and Peanut ones are both nice).
Anyway, just wanted to give you a bit of an insight. It is all pretty overwhelming at first and slow steady changes are better than sudden drastic ones, so start reading food labels for carb content and gradually lowering your carb intake. Feel free to ask any questions that crop up because it does take some time to get your head around it all. I can honestly say that there have been a lot of positives to come from changing my diet and I still enjoy my food, but I do eat very differently to the way I used to.