WhatsApp Messenger is currently not optimised for iPad, and therefore you will need to search for iPhone apps in the App Store search using the filter at the top.
It requires a mac with Xcode and iTunes, and the unencrypted
msgstore.db with the Whatsapp conversations from Android (you can get
it using WhatsApp Key/DB Extractor)
Won’t give much more details as the watoi project link has a README
with the instructions and are easy to follow
Watoi has two limitations though, per its github page:
Media files and shared locations are not imported (got placeholders
instead)
Messages from contacts that changed ids (phone numbers) are
not linked
Best Answer
You could install Bluestacks on your Mac and then install the Android version which you could access through BlueStacks.
Here's how to install it.