Hello Zoey,
Thank you so much for using our theme SuperMagPro. If you want to set the default sidebar please follow the below steps:
Go to Appearance > Customize > Layout Design/Options > Default Sidebar Layout
Please follow this documentation link https://doc.acmethemes.com/supermagpro/#HowtosetDefaultsidebarLayout?
Choose the available options to set the global sidebar layout.
Now, each page or post you created it will automatically created the same layout. But keep in mind that the previously set layout of page or post will not changed.
If you have any problem regarding our theme, please write us for support.
Best Regards,
Acme Supports