PPT change slide theme

Recently, I want to give an oral presentation at a meeting. I found a PPT template on the Internet, but the PPT template has downloaded advertising information, and the presentation of the oral presentation is out of date. Therefore,

we need to rename the theme of the slide.
Open PowerPoint-----View
to open the slideshow
Click on the first master title style in the slice master

, click Rename in the toolbar,

and close the master view after renaming