Whatsapp is linked to the mobile number. If you install it on a non-mobile device, then it can only be a mimic of another device.
That is why it's behaving like a web version. This version has to link to a main device with a sim card / phone number.
You may have to wait a while for the truly windows version, according to this report from indianexpress
Facebook-owned WhatsApp is reportedly working on a desktop version of the app that may allow users to use the messaging platform even when the phone is not connected to the internet. The information comes from a reliable leaker WABetaInfo, which claimed that WhatsApp is building a Universal Windows Platform (UWP) that would work even when the phone is off.
For those who don’t know; WhatsApp can be accessed on a computer via WhatsApp Web app for PC or web.whatsapp.com address on a browser. All you need to do is log-in into the WhatsApp Web and you will be able to receive and send messages via PC without the need to touch your phone.
However, in order to use WhatsApp on PC, you need to have WhatsApp installed on your phone and the device must have internet connectivity.
Additionally, Whatsapp can no longer be installed on several phones after Nov 2021.
Currently, we provide support for and recommend using the following devices:
Android running OS 4.1 and newer
iPhone running iOS 12 and newer
KaiOS 2.5.0 and newer, including JioPhone and JioPhone 2
from Whatsapp faq
On another site,
S3 mini is listed as one of the devices that it will not work on. If your tablet has a lower version of android, then try to update it first.