All perfect praise be to Allaah, the Lord of the worlds. I testify that there is none worthy of worship except Allaah and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and Messenger.
As long as you are able to fast, you are required to make up for the days that you have missed. You are also required to feed a poor person for each missed day that you have delayed beyond its specified time. You cannot clear yourself from you liability unless you do both actions (fasting and feeding) since feeding alone is not enough to make up for the missed days unless you are unable to fast. The number of the missed days can be determined through investigation and diligent effort.
Allaah Knows best.