enable free shipping to users who buy free shipping vouchers(product)

I want to offer free shipping to customers based on the free shipping package they bought and a number of orders.

Here is the complete workflow:-

  1. Admin Creates a Product (voucher) "Free Shipping for 12 orders" (the number of orders can be different)
  2. A user buys this product.
  3. For the next 12 orders the user will get the free delivery applied to his order.
  4. After 12 orders, He will not get the free delivery option and if he wants to have a free delivery option he has to purchase the free shipping product again.