This is one of the ways you can use WhatsApp without a smartphone and android emulator on macOS. The feature however is in beta testing by WhatsApp and is expected to be fully rolled out soon.
You should note that this method will require you to link your device to the WhatsApp web or macOS desktop app at the initial stage after which you can use WhatsApp on MacOS without a smartphone or an android emulator. You can also read on how to use WhatsApp on PC without phone or android emulator.
PS: If you don’t have a smartphone, you may need to borrow one just for the initial steps and after linking you won’t need the device, this method works even when the smartphone you used is offline or logged out of the WhatsApp account. So no worries.
Here’s how to use WhatsApp on macOS without a smartphone or android emulator
Step 1: Download WhatsApp for Mac here – WhatsApp for Mac
Step 2: Download and sign up to WhatsApp on your borrowed smartphone with your phone number.
Step 3: Open WhatsApp on your borrowed smartphone and tap on the three-dotted icon. These are located on the top right corner of the screen. Then Tap on Linked devices.
Step 4: Then tap on “Multi-device beta”. WhatsApp will then show you a page that highlights the limitations of the beta feature for connecting to WhatsApp on MacOS without a smartphone. Tap the Join Beta button and press on the Continue button.
Step 5: Once done, you simply need to link the WhatsApp on a smartphone to your WhatsApp on MacOS, just once, and then thereafter you can use WhatsApp on your MacOs without a smartphone or android emulator.
I hope this is close to helping you achieve what you intended to achieve.