I have a question regarding the kaffarah for breaking a fast on the month of Ramadan. I broke my fast intentionally on one day in Ramadan and I fasted the qaza of this fast after the end of the month of ramadan.

Because I didn't know I had to pay a kaffarah for it, I didn't do anything about this until a couple of years later when I found out that I had to pay the kaffarah. My question is will I have to pay the kaffarah now considering it is now 4 years later or I dont need to pay the kaffarah.

If you were aware that breaking the fast is haram, you have to pay the kaffarah, even after 100 years.