Hi Aparicio,
You can do this. At first i would like to ask which theme are you using ?
go to Dashboard -> Appearance-> Theme – Options ->layout options -> content layout
If you select the sidebar from here then its for all pages. And if you want to select the individual sidebar for specific page then create a page -> at the below of the page there is same content layout (left sidebar, right sidebar , full width etc.)
This selection will be displayed for individual pages.
Thank you!
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