Convert PowerPoint to  PDF File

3. Click Save as Adobe PDF  from the list on the left 

4. Choose the location or folder where you’d like to
      save your document

5. Click Save

6 .Your document should open in Adobe Acrobat, which
    allows you to preview the document.

4. In the "Export As" field,  choose a file name

5. Choose a destination

6. Change the "File Format" to PDF

7. Click Export