Before buying this service, check if it is available in your country, buy it from the Wonet app and then make a call forward from your phone settings to Wonet number in your country that will be shown within the App notification message.
Now in the “Plus” page you can see that the Call Forward is activated (red) button).
You can deactivate and reactivate the call forward from your original number to Wonet number as much as you want within the subscription period; i.e.: one month starting from the date of buying the service.