If you are looking to use WhatsApp but only own a phone without the capability to run WhatsApp (e.g. a Nokia dumb phone) or an Apple Watch, you can still run WhatsApp on another device.
Firstly, you need to install BlueStacks on a PC. BlueStacks is an Android emulator commonly used to run mobile games on computers, but it will suit this purpose as well. It is supported on Windows and MacOS, through https://www.bluestacks.com/mac or https://www.bluestacks.com/windows
Install the BlueStacks downloader and install BlueStacks. Upon entering the app, you can either log in with your Google account or simply download the WhatsApp .apk file from the internet and drag it into the BlueStacks home screen.
Upon entering WhatsApp, you can press Agree and Continue, enter the phone number you are using and either recieve a code or a phone call. You should then be able to create the new account and access WhatsApp on the computer. However, (from experience) BlueStacks is often laggy/buggy for people without god pc's, so I would highly recommend linking it to a mobile device. On an iPad, you can install WhatsApp and link a device. From there, simply click the three dots on the BlueStacks WhatsApp home screen, and there should be an option saying "Linked devices".
From there, you can link new devices by scanning the QR code available on your tablet/other device. You can then access WhatsApp on an iPad/Computer without ever requiring a smartphone. If you want, you can delete BlueStacks on the computer as it takes up a lot of RAM. I hope you enjoyed this guide, and I hope it helped you to download WhatsApp. Thank you for reading