By default, WhatsApp notifies everyone in a conversation about the status of messages. A checkbox system is used to indicate the status. One gray check mark means that the message was sent, two - that the message was successfully delivered. And when the interlocutor has read the message, two gray check marks turn blue. You can't turn this off for group chats, but it's very easy to do it for WhatsApp dialogs.
Block the sending of read receipts
If you don't like the idea of read receipts, then this feature can be turned off for all messages on WhatsApp. The downside of this decision is that WhatsApp will stop showing read receipts for messages you send (apparently, in fairness).
Open WhatsApp and tap the three dots in the upper right corner, then select “Settings”=> "Account"=> "Privacy" and uncheck "Read receipts".
The Topic of Article: How to read a WhatsApp message without the sender knowing it.