1. Download WhatsApp
For doing this open the App Store
and search for “WhatsApp”. Once you found the messenger, click Get or the cloud. The cloud only appears, if you already used this app on your device with this Apple ID before. Then it will install WhatsApp on your device. The download will be completed, when you can see the option Open.
When you open WhatsApp, you will be prompted to register your phone number. Now enter your landline. Please, make sure you are using the correct country code (i.e. +1 for the USA) and skip the zero for the area code (unimportant for the U.S.). In Australia, for example, the number 02 1234 5678 turns into (+61) 2 1234 5678. You can use your land line only for one WhatsApp account. You always need a new number for another WhatsApp account.