The following article introduces you in detail. Create slides from an existing slide in PowerPoint.
Step 1: Open PowerPoint -> go to File -> Open -> select the PowerPoint file to apply:
Step 2: The file to be applied is displayed -> proceed to edit the content of the Silde:
Step 3: After editing the content, the results are:
Step 4: Proceed to save the edited file by clicking File -> Save As:
Step 5: The Save As dialog box appears -> choose a location to save the file and rename the file -> Save:
So with a few simple steps, you can create a presentation from an existing one without spending a lot of time.
Good luck!