Hello from another type 3c; like Wendal I had a fair amount of necrosis damage to my pancreas, gallstones kicking everything off in the beginning. I lasted a few years on not having diabetes but I think all the extra work my pancreas was doing, or what was still working, it decided to go on strike and I quickly developed classic diabetes signs. I was put on insulin a year ago and have learned quite quickly what levels suit me. Every now and again my depleted pancreas decides it can make some background insulin!
My levels of insulin have been everywhere from 1 unit per 20g carbs to 1 unit per 4g carbs... Most of the time it is around 1u to 9g nowadays but also changes during the day. First thing in the morning it is around 1u to 6g carbs until I have digested (with the help of enough creon) the first meal of the day, then it levels out until the end of the day.
With my annual visit to diabetes centre today they asked if I wanted to go to a half unit pen which I said yes to, but because I had just had 5 pens done on prescription this week and lack of pens in stock, they said it would have to wait a bit...
So, it's a slow journey in the beginning as you work out what foods agreed with you, your insulin levels, the variability of insulin requirements over time... But as long as you take note of what you do and how much, you will get there