Hi and welcome to the forum
After you've been diagnosed a while it is likely that your team will start you carb counting, its relatively easy and I haven't been on any course for it like many people have, this will then mean you can adjust your insulin for what you are eating, it gives more freedom, so don't write pasta off the list just yet!
For snacks, at the moment I'd say don't try things that are likely to need covered, so stick to say a handful of nuts, some cold meat and cheese, a few squares of dark chocolate if you like it, the higher the cocoa content the better as there's less carbohydrate and sugars, some people find they can have a snack but not need to inject for it if it is under 10g carbohydrate
As for meals, I'm afraid many will tell you to severely reduce the amount of bread, potatoes, pasta, rice etc that you have, a typical day for me is porridge and raspberries for breakfast, a sandwich and a nature valley protein bar for dinner and then potatoes and some sort of veg with meat/chicken/omelette etc for tea
Hope this has helped a little bit
xx