Answer:
What has 4 fingers and a thumb, but is not living?
I'm a starchy plant tuber that is one of the most important food crops, cooked and eaten fried, such as french fries.
Break it and it gets better, immediately set and harder to break again.
If you have me, you want to tell me. If you tell me, you don't have me.
I'm the start of eternity and the end of space. There are two of me in heaven and one in hell.
I am the fountain from which no one can drink. For many I am considered a necessary link. Like gold to all I am sought for, but my continued death brings wealth for all to want more.