Add Link Buy On WhatsApp

Your Plugin so so simple and it gives everything what we need on the purpose without add to many things. I need your help on your plugin I made a extra button which is called Buy On WhatsApp and worked no problem. The thing is

function sbw_wc_handle_buy_now()

and change it to

function sbw_wc_handle_buy_whapp()

how I can redirect when they click on the button and open it in new window to send message on whatsapp. I try to many ways but I cannot.