Open ps software, File-Open, select the picture with the date to be modified, open the polygonal lasso tool, select the date on the picture according to the date to be modified, press ctrl+j to copy and paste, open the mobile tool, move the copied text to the appropriate position, press ctrl+t on the keyboard to adjust the size, open the eyedropper tool, and click near the text of the background picture to color the background of the picture.