1. Login to admin dashboard.
2. Navigate to Catalog > Products using the sidebar menu.
3. Click Edit button on the product selected.
4. In Products, navigate to Reward Points tab, fill in the points needed to buy the item. After done, click Save / Quick Save button.
Now in the customers' view, they are able to see this in the product page that they will required 2000 reward points to buy this item.
When customers checkout, they are able to use their reward points to buy the item.