How to set the read receipt of iPhone7 SMS?

How to set the iPhone7 SMS after reading it? If you don't know whether the other party has received or seen the short message, you can turn on the function of sending the read receipt by short message on iPhone7. If the setting location is not found, you can see the following. How to set 1 when sending a read SMS on iPhone7? First, we open the settings, and then find the information. 2. After opening, we can open the ellipse on the right side of the column of sending the read receipt.