Extract... (Edit/Pages menu)
Select Pages to access the Extract... command, as below:
Use this command to extract a page or a range of pages of the currently opened PDF and save them as another separate PDF file. When extracting pages with this command, the pages in the original PDF will remain unaltered.
In the Extract Pages dialog, specify the first and last page of the page range you need. Then click on Extract. A dialog will appear where you can then save the extracted pages as a separate PDF document to your computer.