I expect you’ll be kept on the same dose of insulin and 50g carbs per meal for a while so that the medical team can see how you respond once your body’s adjusted to using insulin. As others have said, something like Carbs and Cals, which you can get as an app, will help you to keep to 50g per meal. You’ll also need scales that weigh in grams and have a function that allows you to revert to zero so you can weigh each kind of carb you put on your plate. There may be shops that sell them where you live? 50g is generous, which is good as you may get hungry now that there’s a chance your body can use more of the carbs you eat.
It’s also a good idea to keep a record of what your blood sugars are before you eat and about three to four hours afterwards. Note the times on the record. When the DSN sees you again they’ll be able to use your records to work out what doses of insulin you’ll probably need to get your blood sugars at a reasonable level.
It can feel rough to begin with. Commiserations. At least now you’ve got started on insulin you should begin to feel better and I hope that before too long you’ll be in your stride with the T1 stuff.
What are you studying? There are a few of us who were diagnosed when we were students.