Refund and exchange both are different points and the button of both points also different but not difficult to understand.
If you want to visible Refund Button then follow these steps. You can easily go to the WooCommerce -> Settings -> RAEsetting ->Refund Products and set the following points.
1)Enable Refund Request.
2)Set the maximum number of days.
3)Select the order status in which the order can be Refunded.
If you want to visible Exchange Button then follow these steps. You can easily go to the WooCommerce -> Settings -> RAEsetting ->Exchange Products and set following points.
1)Enable Exchange Request.
2)Set Maximum Number of Days.
3)Select the order status in which the order can be Exchanged.