Some of your question can only be answered by your countries own medical guidelines which may be much different from where I live (Canada)

Here, to even be eligible you would have to gain insanely great control of your blood sugar before you would "make the list"

Kidneys are in short supply and they want to give it to someone with the best chance of a positive outcome

Uncontrolled diabetes "kills kidneys" so they are not going to give it to someone who has not shown they are willing to do the hard work themselves to make it viable

If you somehow managed to get on the list and won the lottery and got the transplant there is an (almost) 70% chance you would live 5 years longer - it's not buying you decades, but 5 years is a whole lot more than zero

Statistically your life expectancy drops to 5 years when you start dialysis - a transplant can add 5 more years to that

Sorry - cold numbers but something you and the health care system need to consider before adding someone to the list because there is not enough organs to go around

Just like an alcoholic is unlikely to get a new liver, an uncontrolled diabetic is not going to get a kidney. So your best chance would be to gain excellent control "first" (or show that you are absolutely committed)