Question: how can i block someone on whatsapp group?
Answer: Open WhatsApp.
Go to the group.
Tap on group info.
Tap on the contact that you want to block. ... 
Scroll down and choose the block option on Iphone.
On an Android device, click on chat option menu button (three dots).
Now click "More" and then select "Block" option.
A pop up box will appear.