"I am ready to die."
Translation:Jeg er klar til at dø.
"Til at" is usually used for statements in the near future, like "Vi skal til at spise kartofler" (We are going to eat potatoes) and "Hjælp os hernede til at forstå" (Help us down here understand [in the near future]).
"Til at" is also used to describe skills/abilities, like "Jeg er god til at cykle" and "Mange vampyrer opdrages til at drikke blod fra dyr" (the ability to drink blood).
So because this sentence (I am ready to die) is referencing something in the near future and is also kind of like an ability (like the ability to die, which is a bit weird when you put it that way), you would use "til at dø".