This article will help explain how you can set your redemption conditions.
This is the minimum point the customer must have to make a redemption, the redemption rate is 100 points equals $1, so you can set the minimum points before redemption to 500 points, As soon as this is set it means that the customer has to have at least 500 points to make a redemption.
This is the maximum discount the customer can get when redeeming their points to make a purchase for any product. For example, if a customer wants to buy a product of $10 and the customer has 1000 points. 1000 points equal $10 if you set the maximum discount per redemption to 50%, the customer can only make redemption of 500 points which equals $5.