Blockchain Green Wallet help

Hi. I just created a Green wallet to try out and when I click receive to view my bitcoin address, I also see at the top right of the QR, a reverse 2 arrow icon. When I prees it, it seems to switch wallet addreses, so I do not know which address to send too. I have attached a few pictures for reference. Here is what happens exactly when I tap the arrows icon. I tap it 3 times to cycle through the different addresses. So, as you can see, each one is different, and I don't know which to withdraw from, and what one to enter and set as my wallet address in tool, when sending funds to someone else, or receiving. What is this icon used for? Thank you in advance for the help!