How does iphone delete a large number of SMS messages?

The method for deleting a large number of short messages on this brand mobile phone is as follows:

Open the SMS application of iPhone, then press and hold the first SMS to be deleted, and select "More". A blue circle will appear, indicating that you have entered editing mode. At this point, you can continue to select other short messages to delete, and select them by touching the box in front of each short message. The selected SMS will display a check mark, and then click the "trash can" icon at the bottom of the screen to confirm the deletion.