Preview displays the pages as if it were a book. This is by design. Apple has not changed this in spite of users asking for the flexibility you want.
You should explore other apps. Some behave like Preview, some behave with pages 1 & 2 at the start (no choice) and some give you the choice.
Apps that are known to give a choice of two-page views:
Adobe Acrobat Reader in View > Page Display > Show Cover Page (disable or enable)menu toggle.
Foxit Reader in View > Page Display > Separate Cover Page menu commandtoggle.
Skim in PDF > PDF Display > Book mode menu toggle.
Right now I don't know of others!