Privacy is not the point of OP’s question. A good answer would’ve been saying there is no WhatsApp client for Linux, and then (optionally) explaining that Signal has a desktop client and is a also privacy-respecting choice. Insulting OP by stating “You should not use this or that” is such a StackOverflow thing and helps nobody.

Edit: Just to make sure: I’ve never used WhatsApp and never will use it.