If you mean featured on a shelf, it’s just a matter if your story fits an upcoming shelf theme and is of a decent quality (helps if many people nominate it too).
For Episode to purchase your story and feature it, that’s different:
If you mean how do you access the Writer’s Payment Program:
“500,000 general reads (half a million) across all of your published stories in the last 60 days.
OR
100,000 gem reads & 50,000 gems used
across all of your published stories in the last 60 days.”